Practice Questions/Helpful Tips (NUR3028 Medication Calculation Review)

Calculating PO (Tablets/Capsules) Doses Order: 0.4 g PO every 8 hrs Available: 200 mg/capsule How many capsules should the nurse administer?

Set Up an Equation and Cancel Out "g" 1 g = 1,000 mg -> 0.4 g • 1,000 mg/1 g -> 0.4/8 hr • 1,000 mg/1 Based on the Information Provided in the Question, Cancel Out "mg" 0.4 • 1,000 mg/1 • 1 capsule/200 mg -> 0.4 • 1,000/1 • 1 capsule/200 Multiply (0.4 • 1,000 capsule)/200 = 2 capsules

Dosage Calculation A patient has a primary IV of dextrose in water 1,000 mL to be infused over 24 hours. What would be the drip rate (gtts/min) using tubing with a drop factor of 60? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "hr" 1,000 mL/24 hr • 1 hr/60 min -> 1,000 mL/24 • 1/60 min Based on the Information Provided in the Question, Cancel Out "mL" 1,000 mL/24 • 1/60 min • 60 gtts/1 mL -> 1,000/24 • 1/60 min • 60 gtts/1 Multiply and Divide (1,000 • 60 gtts)/(24 • 60 min) = 60,000 gtts/1,440 min -> 60,000 gtts/1,440 min = 41.66 gtts/min Round to the Nearest Whole Number 41.66 gtts/min -> 42 gtts/min

Drop Factor Calculation Order for 500 mL NS to infuse over 4 hours. Drop factor of IV tubing is 12 gtt/mL. How many gtt/min should be delivered to the patient?

Set Up an Equation and Cancel Out "hr" 500 mL/4 hr • 1 hr/60 min -> 500 mL/4 • 1/60 min Based on the Information Provided in the Question, Cancel Out "mL" 500 mL/4 • 1/60 min • 12 gtt/1 mL -> 500/4 • 1/60 min • 12 gtt/1 Multiply (500 • 12 gtt)/(4 • 60 min) = 6,000 gtt/240 min Divide 6,000 gtt/240 min = 25 gtt/min

Parenteral Medication Dosage Calculation You need to administer prochlorperazine (Compazine) 10 mg IM to a nauseated patient. You have on hand Compazine 5 mg/mL. How many mL would you administer per dose? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "mg" 1 mL/5 mg • 10 mg/1 -> 1 mL/5 • 10/1 Multiply and Divide 10 mL/5 = 2 mL

Dosage Calculation A patient has a bottle of warfarin (Coumadin) 5 mg tablets at home. After his most recent international normalized ratio (INR), the doctor calls and tells him to take 7.5 mg/day. How many tablets should the patient take? (Round the answer to one decimal place)

Set Up an Equation and Cancel Out "mg" 1 tab/5 mg • 7.5 mg/1 day -> 1 tab/5 • 7.5/1 day Multiply (1 • 7.5 tab)/5 day = 7.5 tab/5 day Divide 7.5 tab/5 day = 1.5 tab/day

Oral Medication Dosage Calculation You need to administer 400 mg of erythromycin (Erythrocin) PO. You have on hand a suspension of 125 mg/5 mL. How many mL will you prepare?

Set Up an Equation and Cancel Out "mg" 5 mL/125 mg • 400 mg/1 -> 5 mL/125 • 400/1 Multiply and Divide (5 • 400 mL)/125 = 2,000 mL/125 -> 2,000 mL/125 = 16 mL

Calculating IV/IM/Subcutaneous Doses Order: 5,000 units heparin subcutaneously every 8 hrs Available: 10,000 units/mL #1: How many mL does the nurse give with each dose? #2: How many mL does the nurse give in 24 hrs?

Set Up an Equation and Cancel Out "units" 5,000 units • 1 mL/10,000 units -> 5,000 • 1 mL/10,000 Multiply (5,000 • 1 mL)/10,000 = 5,000 mL/10,000 Divide 5,000 mL ÷ 10,000 = #1: 0.5 mL Set Up an Equation to Find How Many mL are Given in 24 Hrs and Cancel Out "hr" 0.5 mL/8 hr • 24 hr -> 0.5 mL/8 • 24 Multiply (0.5 • 24 mL)/8 = 12/8 mL Divide 12 ÷ 8 mL = #2: 1.5 mL

Body Surface Area/Drug Administration Order: 120 mg/m^2 PO stat Available/Drug Label: 8 mg/mL If the patient's body surface area is 2.1 m^2, how many mL will the nurse administer?

Approach #1 Multiply 120 mg/m^2 • 2.1 m^2 = 252 mg Divide 252 mg ÷ 8 mg/mL = 31.5 mL Approach #2 Set Up an Equation 2.1 m^2/1 = x/y mL Based on the Information Provided in the Question, Cancel Out "m^2" 2.1 m^2/1 • 120 mg/1 m^2 -> 2.1/1 • 120 mg/1 Based on the Information Provided in the Question, Cancel Out "mg" 2.1/1 • 120 mg/1 • 1 mL/8 mg -> 2.1/1 • 120/1 • 1 mL/8 Multiply (2.1 • 120 mL)/8 = 252 mL/8 Divide 252 mL ÷ 8 = 31.5 mL

IV Flow Rates Determine the flow rate in mL/hr for the following: Order: 1,000 mL NS to infuse in 8 hours

Set Up an Equation 1,000 mL/8 hr Divide 1,000 mL/8 hr = 125 mL/hr

Dosage Calculation Your patient needs 2,000 mL of D5W IV over 24 hours, to be delivered with tubing set with a drop factor of 15. How many drops per minute will you set for an infusion rate? (Round to the Nearest Whole Number)

Set Up an Equation and Cancel Out "hr" 2,000 mL/24 hr • 1 hr/60 min -> 2,000 mL/24 • 1/60 min Based on the Information Provided in the Question, Cancel Out "mL" 2,000 mL/24 • 1/60 min • 15 gtts/1 mL -> 2,000/24 • 1/60 min • 15 gtts/1 Multiply and Divide (2,000 • 15 gtts)/(24 • 60 min) = 30,000 gtts/1,440 min -> 30,000 gtts/1,440 min = 20.83 gtts/min Round to the Nearest Whole Number 20.83 gtts/min -> 21 gtts/min

Tablets and Capsules The patient has been prescribed Lanoxin 0.5 mg po every day. The pharmacy supplies 0.25 mg tablets. How many tablets would the nurse administer per dose?

Set Up an Equation and Cancel Out "mg" 1 tab/0.25 mg • 0.5 mg/1 -> 1 tab/0.25 • 0.5/1 Multiply and Divide (0.5 tab)/0.25 = 2 tab

Dosage Calculation The physician orders an IV with heparin at 700 units/hr. You have a bag with 100 units/mL of solution. How many milliliters per hour will you set on the IV infusion controller?

Set Up an Equation and Cancel Out "units" 700 units/1 hour • 1 mL/100 units -> 700/1 hour • 1 mL/100 Multiply and Divide 700 mL/100 hr = 7 mL/hr

Parenteral Medication Dosage Calculation A health care provider orders fentanyl (Sublimaze) 0.05 mg IV bolus; Reconstitution instructions: Constitute to Fentanyl 100 micrograms/2.3 mL with 2.4 mL of 5% Dextrose Water for Injection. How many mL will you administer? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "mcg" 2.3 mL/100 mcg • 1,000 mcg/1 mg -> 2.3 mL/100 • 1,000/1 mg Based on the Information Provided in the Question, Cancel out "mg" 2.3 mL/100 • 1,000/1 mg • 0.05 mg/1 -> 2.3 mL/100 • 1,000/1 • 0.05/1 Multiply and Divide (2.3 • 1,000 • 0.05 mL)/100 = 115 mL/100 -> 115 mL/100 = 1.15 mL Round to the Nearest Tenth 1.15 mL -> 1.2 mL

Dosage Calculation Your patient needs 2,000 mL of saline IV over 4 hours for severely deficient fluid volume. How many milliliters per hour will you set on a controller?

Set Up an Equation 2,000 mL/4 hr = x mL/1 hr Divide 2,000 mL/4 hr = 500 mL/hr

Oral Medication Dosage Calculation A patient is instructed to take acetaminophen (Tylenol) liquid (elixir) 650 mg q.i.d. The elixir is 160 mg/5 mL. How many milliliters per dose should the patient take? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "mg" 5 mL/160 mg • 650 mg/1 -> 5 mL/160 • 650/1 Multiply and Divide (5 • 650 mL)/160 = 3,250/160 mL -> 3,250/160 mL = 20.31 mL Round to the Nearest Whole Number 20.31 mL -> 20 mL

Oral Medication Dosage Calculation Your order reads ergocalciferol (Calciferol) 225,000 units PO daily. You have on hand ergocalciferol in 50,000 unit tablets. How many tablet(s) will you administer?

Set Up an Equation and Cancel Out "unit" 1 tab/50,000 unit • 225,000 unit/1 -> 1 tab/50,000 • 225,000/1 Multiply and Divide 225,000 tab/50,000 = 4.5 tab

Tablets and Capsules A doctor prescribed Levoxyl 0.6 mg po q8h. The pharmacy dispenses 300 mcg tablets. #1: How many tablets would the nurse administer per dose? #2: How many tablets would the nurse administer per day?

Set Up an Equation and, Using Conversions, Cancel Out "mcg" 1 tab/300 mcg • 1,000 mcg/1 mg -> 1 tab/300 • 1,000/1 mg Based on the Information Provided in the Question, Cancel Out "mg" 1 tab/300 • 1,000/1 mg • 0.6 mg/1 -> 1 tab/300 • 1,000/1 • 0.6/1 Multiply and Divide (1,000 • 0.6 tab)/300 = 600 tab/300 -> 600 tab/300 = #1: 2 tab Set Up an Equation to Find How Many Tablets are Administered PER DAY and Cancel Out "hr" 2 tab/8 hr • 24 hr/1 day -> 2 tab/8 • 24/1 day Multiply and Divide (2 • 24 tab)/8 = 48 tab/8 -> 48 tab/8 = #2: 6 tab

Oral Medication Dosage Calculation A patient is placed on methadone (Methadose) maintenance therapy of 15 mg/day PO. It is supplied as 10 mg in 5 mL oral solution. How many milliliters should you instruct the patient to take? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 5 mL/10 mg • 15 mg -> 5 mL/10 • 15 Multiply and Divide (5 • 15 mL)/10 = 75/10 mL -> 75/10 mL = 7.5 mL

Parenteral Medication Dosage Calculation A health care provider orders Heparin 7,855 units sub cut b.i.d.; Available: Heparin 10,000 units per mL. How many mL will you administer? (Round to the nearest hundredth)

Set Up an Equation and Cancel Out "units" 1 mL/10,000 units • 7,855 units/1 -> 1 mL/10,000 • 7,855/1 Multiply and Divide 7,855 mL/10,000 = 0.7855 mL Round to the Nearest Hundredth 0.7855 mL -> 0.79 mL

Parenteral Medication Dosage Calculation A patient with bacterial infection is ordered ceftazidime (Fortaz) 250 mg IM. The vial contains 500 mg powder with directions to add 1.5 mL of sterile water for a total volume of 1.8 mL. How many mL will you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1.8 mL/500 mg • 250 mg/1 -> 1.8 mL/500 • 250/1 Multiply and Divide (1.8 mL • 250)/500 = 450 mL/500 -> 450 mL/500 = 0.9 mL

Oral Medication Dosage Calculation You are providing home care for a patient who needs 15 mL of magnesium hydroxide/aluminum hydroxide (Maalox) PO. She has only standard measuring spoons in the house. How many tablespoon(s) do you instruct her to take her dose? (Round to the nearest whole number)

Set Up an Equation and, Using Conversions, Cancel Out "mL" 15 mL/1 • 1 Tbsp/15 mL -> 15/1 • 1 Tbsp/15 Multiply and Divide 15 Tbsp/15 = 1 Tbsp

Oral Medication Dosage Calculation A health care provider orders digoxin (Lanoxin) 0.25 mg po daily; Available: Digoxin 125 mcg tabs (scored.) How many tab(s) will you administer for this dose?

Set Up an Equation and, Using Conversions, Cancel Out "mcg" 1 tab/125 mcg • 1,000 mcg/1 mg -> 1 tab/125 • 1,000/1 mg Based on the Information Provided in the Question, Cancel Out "mg" 1 tab/125 • 1,000/1 mg • 0.25 mg/1 -> 1 tab/125 • 1,000/1 • 0.25/1 Multiply and Divide (1,000 • 0.25 tab)/125 = 250 tab/125 -> 250 tab/125 = 2 tab

Dosage Calculation The physician orders alprazolam (Xanax) 0.5 mg PO. You have on hand Xanax 0.25 mg tablets. How many tablet(s) will you give?

Set Up an Equation 0.5 mg/0.25 mg = x tab Divide 0.5 mg/0.25 mg = 2 tab

IV Pump Calculation Order: 1,000 mL NS to infuse over 6 hours What is the IV pump rate in mL/hr? Round to the nearest whole number

Set Up an Equation 1,000 mL/6 hrs = mL/hr Divide 1,000 ÷ 6 = 166.67 mL/hr Round to the Nearest Whole Number 166.67 mL/hr -> 167 mL/hr

Infusion Pumps and Flow Rates Order: 1.5 L of normal saline, continuous IV, for 48 hours A particular infusion pump is programmed to deliver fluids based on mL/hour. what should the pump setting be for this order?

Set Up an Equation Flow Rate = Volume/Time -> 1.5 L/48 hr Divide 1.5 L ÷ 48 hr = 0.03125 L/hr Set Up a 2nd Equation to Convert L/hr to mL/hr and Cancel Out "L" 1 L = 1,000 mL -> 0.03125 L/1 hr • 1,000 mL/1 L -> 0.03125/1 hr • 1,000 mL/1 Multiply (0.03125 • 1,000 mL)/1 hr = 31.25 mL/hr Round to the Nearest Whole Number (If Applicable) 31.25 mL/hr -> ~31 mL/hr

Calculating PO (Liquid Medication) Doses Order: 0.5 g PO every 12 hrs Available: 250 mg/5 mL How many mL should the nurse administer?

Set Up an Equation and Cancel Out "g" 0.5 g • 1,000 mg/1 g -> 0.5 • 1,000 mg/1 Based on the Information Provided in the Question, Cancel Out "mg" 0.5 • 1,000 mg/1 • 5 mL/250 mg -> 0.5 • 1,000/1 • 5 mL/250 Multiply (0.5 • 1,000 • 5 mL)/250 = 2,500/250 mL Divide 2,500 ÷ 250 mL = 10 mL

IV Pump Calculation IV infusion is running at 125 mL/hr. How many hours will it take a 500 mL bag of NS to infuse?

Set Up an Equation and Cancel Out "mL" 500 mL/1 • 1 hr/125 mL -> 500/1 • 1 hr/125 Multiply (500 • 1 hr)/125 = 500 hr/125 Divide 500 hr/125 = 4 hr

Drug Calculations Involving Reading Drug Labels Levoxyl is prescribed to a hypothyroid patient, 12.5 mcg/day. How many tablets should be given to this patient per day?

Set Up an Equation and Cancel Out "mcg" 12.5 mcg/1 day • 1 tab/50 mcg -> 12.5/1 day • 1 tab/50 Multiply and Divide 12.5 tab/50 day = 0.25 tab/day

Parenteral Medication Dosage Calculation You have on hand enoxaparin (Lovenox) 30 mg/0.3 mL. You need to administer 1 mg/kg SC. Your patient weighs 200 pounds. How many mL will you draw into a syringe? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 0.3 mL/30 mg • 1 mg/1 kg -> 0.3 mL/30 • 1/1 kg Using Conversions, Cancel Out "kg" 0.3 mL/30 • 1/1 kg • 1 kg/2.2 lbs -> 0.3 mL/30 • 1/1 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 0.3 mL/30 • 1/1 • 1/2.2 lbs • 200 lbs/1 -> 0.3 mL/30 • 1/1 • 1/2.2 • 200/1 Multiply and Divide (0.3 • 200 mL)/(30 • 2.2) = 60 mL/66 -> 60 mL/66 = 0.9 mL

Parenteral Medication Dosage Calculation Atropine 0.6 mg IM is ordered preoperatively. It is supplied as 0.4 mg/mL. How many milliliters should you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 mL/0.4 mg • 0.6 mg/1 -> 1 mL/0.4 • 0.6/1 Multiply and Divide 0.6 mL/0.4 = 1.5 mL

Parenteral Medication Dosage Calculation A patient is admitted to the emergency room with a fractured leg. The physician orders morphine 15 mg IM stat. You have on hand morphine 10 mg/mL. How many milliliters will you administer?

Set Up an Equation and Cancel Out "mg" 1 mL/10 mg • 15 mg/1 -> 1 mL/10 • 15/1 Multiply and Divide 15 mL/10 = 1.5 mL

Parenteral Medication Dosage Calculation You have an order for diphenhydramine hydrochloride (Benadryl) 40 mg IM now. You have on hand Benadryl 25 mg/mL. How many milliliter(s) do you prepare? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 mL/25 mg • 40 mg/1 -> 1 mL/25 • 40/1 Multiply and Divide 40 mL/25 = 1.6 mL

Parenteral Medication Dosage Calculation You need to administer lorazepam (Ativan) 3 mg IM to an agitated patient. You have on hand 4 mg/mL. How much do you prepare in mL? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 mL/4 mg • 3 mg/1 -> 1 mL/4 • 3/1 Multiply and Divide 3 mL/4 = 0.8 mL

Parenteral Medication Dosage Calculation You need to administer 125 mg of methylprednisolone sodium succinate (Solu-Medrol) IV push bid to a patient with acute exacerbation of chronic obstructive pulmonary disease. You have on hand 40 mg/mL. How much do you prepare in mL? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 mL/40 mg • 125 mg/1 -> 1 mL/40 • 125/1 Multiply and Divide 125 mL/40 = 3.1 mL

Parenteral Medication Dosage Calculation Your order reads labetalol 40 mg IV push every 10 minutes until blood pressure is lower than 140/90 mm Hg. You have labetalol 5 mg/mL available. How many mL should you prepare the correct dose? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "mg" 1 mL/5 mg • 40 mg/1 -> 1 mL/5 • 40/1 Multiply and Divide 40 mL/5 = 8 mL

Parenteral Medication Dosage Calculation You have on hand diazepam (Valium) 5 mg/mL. You need to administer 8 mg IV push stat. to a patient having a seizure. How many mL should you draw into the syringe? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 mL/5 mg • 8 mg/1 -> 1 mL/5 • 8/1 Multiply and Divide 8 mL/5 = 1.6 mL

Parenteral Medication Dosage Calculation The physician orders meperidine (Demerol) 75 mg IM every 4 to 6 hours prn for a patient admitted with acute cholecystitis. You have on hand meperidine 50 mg/mL. How much will you give? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 mL/50 mg • 75 mg/1 -> 1 mL/50 • 75/1 Multiply and Divide 75 mL/50 = 1.5 mL

Parenteral Medication Dosage Calculation A health care provider prescribes phenobarbital (Luminal) supplied as 60 mg/mL. You need to administer 160 mg IV stat. How many milliliters should you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 mL/60 mg • 160 mg/1 -> 1 mL/60 • 160/1 Multiply and Divide 160 mL/60 = 2.7 mL

Parenteral Medication Dosage Calculation A patient is receiving 60 mg of methylprednisolone (Medrol) IM every 8 hours. You have on hand 75 mg/mL. How much will you draw up? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 mL/75 mg • 60 mg/1 -> 1 mL/75 • 60/1 Multiply and Divide 60 mL/75 = 0.8 mL

Dosage Calculation You have available lorazepam (Ativan) 0.5 mg tablets, and you need to administer 1 mg PO. How many tablet(s) will you administer?

Set Up an Equation and Cancel Out "mg" 1 mg • 1 tab/0.5 mg -> 1 • 1 tab/0.5 Multiply and Divide 1 • 1 tab/0.5 = 1 tab/0.5 -> 1 tab/0.5 = 2 tab

Drug Calculations Involving Reading Drug Labels Phenobarbital is to be given to a patient at 45 mg/dose tid. #1: How many tablets will be given in one dose? #2: How many tablets will be given in one day?

Set Up an Equation and Cancel Out "mg" 1 tab/15 mg • 45 mg/1 dose -> 1 tab/15 • 45/1 dose Multiply and Divide 45 tab/15 dose = #1: 3 tab/dose Set Up an Equation to Find How Many Tablets are Given in a DAY and Cancel Out "dose" 3 tab/1 dose • 3 dose/1 day -> 3 tab/1 • 3/1 day Multiply and Divide (3 • 3 tab)/1 day = #2: 9 tab/day

Oral Medication Dosage Calculation You need to administer 40 mg of furosemide (Lasix) PO. You have on hand Lasix 20 mg tablets. How many tablet(s) should you give?

Set Up an Equation and Cancel Out "mg" 1 tab/20 mg • 40 mg/1 -> 1 tab/20 • 40/1 Multiply and Divide 40 tab/20 = 2 tab

Oral Medication Dosage Calculation Diltiazem (Cardizem) 90 mg PO t.i.d. is ordered for a patient with hypertension. It is supplied in 60 mg scored tablets. How many tablet(s) should you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 tab/60 mg • 90 mg/1 -> 1 tab/60 • 90/1 Multiply and Divide 90 tab/60 = 1.5 tab

Parenteral Medication Dosage Calculation A patient is receiving 160 mg of methylprednisolone (Medrol) IM every 12 hours. You have on hand two vials that each contains 125 mg/2 mL. How much will you draw into a syringe?

Set Up an Equation and Cancel Out "mg" 2 mL/125 mg • 160 mg/1 -> 2 mL/125 • 160/1 Multiply and Divide (2 • 160 mL)/125 = 320 mL/125 -> 320 mL/125 = 2.6 mL

Parenteral Medication Dosage Calculation An order reads furosemide (Lasix) 40 mg IV push. You have on hand Lasix 20 mg/2 mL. How many mL would you administer per dose?

Set Up an Equation and Cancel Out "mg" 2 mL/20 mg • 40 mg/1 -> 2 mL/20 • 40/1 Multiply and Divide (2 • 40 mL)/20 = 80 mL/20 -> 80 mL/20 = 4 mL

Parenteral Medication Dosage Calculation You have an order for furosemide (Lasix) 80 mg IV every morning. You have on hand Lasix 20 mg in 2 mL sterile water. How many milliliters should you prepare? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "mg" 2 mL/20 mg • 80 mg/1 -> 2 mL/20 • 80/1 Multiply and Divide (2 • 80 mL)/20 = 160 mL/20 -> 160 mL/20 = 8 mL

Dosage Calculation You need to administer 250 mg of erythromycin (Erythrocin) PO. You have on hand 0.5 g tablets. How many tablet(s) will you give?

Set Up an Equation and Cancel Out "mg" 250 mg/1 • 1 g/1,000 mg -> 250/1 • 1 g/1,000 Based on the Information Provided in the Question, Cancel Out "g" 250/1 • 1 g/1,000 • 1 tab/0.5 g -> 250/1 • 1/1,000 • 1 tab/0.5 Multiply (250 • 1 tab)/(1,000 • 0.5) = 250/500 tab Divide 250/500 tab = 0.5 tab

Dosage Calculation You have an order to administer 40 mg of methadone (Dolophine) SC for opioid detoxification. You have on hand 30 mg/mL. How much mL should you draw into the syringe? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 40 mg/1 • 1 mL/30 mg -> 40/1 • 1 mL/30 Multiply and Divide (40 • 1 mL)/30 = 40 mL/30 -> 40 mL/30 = 1.3333 mL Round to the Nearest Tenth 1.3333 mL -> 1.3 mL

Dosage Calculation The physician writes a "now" order for codeine 45 mg IM for a patient with a vertebral compression fracture. You have on hand codeine 60 mg/2 mL. How many milliliters should you give? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 45 mg • 2 mL/60 mg -> 45 • 2 mL/60 Multiply and Divide (45 • 2 mL)/60 = 90 mL/60 -> 90 mL/60 = 1.5 mL

Oral Medication Dosage Calculation Amoxil (amoxicillin) suspension 180 mg PO b.i.d. is ordered for a patient who cannot swallow pills. It is supplied as 125 mg/5 mL. How many milliliters should you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 5 mL/125 mg • 180 mg/1 -> 5 mL/125 • 180/1 Multiply and Divide (5 • 180 mL)/125 = 900 mL/125 -> 900 mL/125 = 7.2 mL

Drug Calculations Involving Reading Drug Labels A patient is to receive 350 mg of Augmentin per dose. Determine the proper amount in mL the patient is to receive.

Set Up an Equation and Cancel Out "mg" 5 mL/125 mg • 350 mg/1 -> 5 mL/125 • 350/1 Multiply and Divide (5 • 350 mL)/125 = 1,750 mL/125 -> 1,750 mL/125 = 14 mL

Drug Calculations Involving Reading Drug Labels A 138 lb adult with pneumonia is to receive 500 mg Ceclor every 8 hours. #1: How many mL will the patient receive per dose? #2: How many mL will the patient receive per day?

Set Up an Equation and Cancel Out "mg" 5 mL/250 mg • 500 mg/1 dose -> 5 mL/250 • 500/1 dose Multiply and Divide (5 • 500 mL)/250 dose = 2,500 mL/250 dose -> 2,500 mL/250 dose = #1: 10 mL/dose Set Up an Equation to Find How Many mL are Received PER DAY and Cancel Out "hr" 10 mL/8 hr • 24 hr/1 day -> 10 mL/8 • 24/1 day Multiply and Divide (10 • 24 mL)/8 day = 240 mL/8 day -> 240 mL/8 day = #2: 30 mL/day

Dosage Calculation You need to administer furosemide (Lasix) 2 mg/min via continuous IV infusion on a controller. Pharmacy has sent a bag of Lasix 400 mg diluted in D5W 250 mL. How many milliliters per hour will you set on the controller?

Set Up an Equation and Cancel Out "min" 2 mg/1 min • 60 min/1 hr -> 2 mg/1 • 60/1 hr Based on the Information Provided in the Question, Cancel out "mg" 2 mg/1 • 60/1 hr • 250 mL/400 mg -> 2/1 • 60/1 hr • 250 mL/400 Multiply and Divide (2 • 60 • 250 mL)/400 hr = 30,000/400 hr -> 30,000/400 hr = 75 mL/hr

Parenteral Medication Dosage Calculation You have on hand penicillin 300,000 units/mL. Your order reads penicillin 1,000,000 units IM. How will you fill the syringe in mL? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "units" 1 mL/300,000 units • 1,000,000 units/1 -> 1 mL/300,000 • 1,000,000/1 Multiply and Divide 1,000,000 mL/300,000 = 3.3 mL

Parenteral Medication Dosage Calculation A patient is receiving 250,000 units of penicillin G (Pfizerpen) IM every 6 hours. You have on hand 300,000 units/mL. How much will you draw into the syringe? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "units" 1 mL/300,000 units • 250,000 units/1 -> 1 mL/300,000 • 250,000/1 Multiply and Divide 250,000 mL/300,000 = 0.8 mL

Parenteral Medication Dosage Calculation Your patient needs 12,000 units of heparin SC. You have on hand 5,000 units/mL. How much will you inject? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "units" 1 mL/5,000 units • 12,000 units/1 -> 1 mL/5,000 • 12,000/1 Multiply and Divide 12,000 mL/5,000 = 2.4 mL

Parenteral Medication Dosage Calculation Your patient has an order for heparin SC 2,500 units bid. You have on hand heparin 5,000 units/mL. How many milliliters will you administer in a day? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "units" 1 mL/5,000 units • 2,500 units/1 -> 1 mL/5,000 • 2,500/1 Multiply and Divide 2,500 mL/5,000 = 0.5 mL Set Up an Equation to Find How Many mL are Administer in a DAY and Cancel Out "dose" 0.5 mL/1 dose • 2 dose/1 day -> 0.5 mL/1 • 2/1 day Multiply and Divide (0.5 • 2 mL)/1 day = 1 mL/day

Parenteral Medication Dosage Calculation You have an order for heparin 3,000 units SC every 12 hours. You have available 5,000 units/mL. How many milliliters will you give? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "units" 1 mL/5,000 units • 3,000 units/1 -> 1 mL/5,000 • 3,000/1 Multiply and Divide 3,000 mL/5,000 = 0.6 mL

Parenteral Medication Dosage Calculation A health care provider prescribes Heparin 4,390 units sub cut bid; Available: Heparin 5,000 USP units per mL in 10 mL. How many mL will you administer? (Round to the nearest hundredth)

Set Up an Equation and Cancel Out "units" 1 mL/5,000 units • 4,390 units/1 -> 1 mL/5,000 • 4,390/1 Multiply and Divide 4,390 mL/5,000 = 0.878 mL Round to the Nearest Hundredth 0.878 mL -> 0.88 mL

Parenteral Medication Dosage Calculation Your order reads penicillin 1.2 million units IM daily. You have penicillin 500,000 units/mL. How many mL should you prepare the correct dose? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "units" 1 mL/500,000 units • 1,200,000 units/1 -> 1 mL/500,000 • 1,200,000/1 Multiply and Divide 1,200,000 mL/500,000 = 2.4 mL

Oral Medication Dosage Calculation You have on hand ergocalciferol (Calciferol) liquid 8,000 units/2 mL. Your order reads ergocalciferol 225,000 units PO daily. How many mL should you prepare the correct dose? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "units" 2 mL/8,000 units • 225,000 units/1 -> 2 mL/8,000 • 225,000/1 Multiply and Divide (2 • 225,000 mL)/8,000 = 450,000/8,000 mL -> 450,000/8,000 mL = 56.25 mL Round to the Nearest Whole Number 56.25 mL -> 56 mL

Parenteral Medication Dosage Calculation You need to administer amphotericin B (Fungizone) 0.5 mg/kg IV daily to a patient with histoplasmosis who weighs 236 pounds. How many milligrams should you expect to administer each day? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "kg" 0.5 mg/1 kg • 1 kg/2.2 lbs -> 0.5 mg/1 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 0.5 mg/1 • 1/2.2 lbs • 236 lbs/1 -> 0.5 mg/1 • 1/2.2 • 236/1 Multiply and Divide (0.5 • 236 mg)/2.2 = 118 mg/2.2 -> 118 mg/2.2 = 53.6 mg

Parenteral Medication Dosage Calculation You have an order for 500 mg vancomycin (Vancocin) I.V.P.B. every 6 hours for a patient who weighs 120 lbs. You know that you can safely administer up to 40 mg/kg/day. Is the order safe?

Set Up an Equation and, Using Conversions, Cancel Out "lbs" 500 mg/120 lbs • 2.2 lbs/1 kg -> 500 mg/120 • 2.2/1 kg Multiply and Divide (500 • 2.2 mg)/120 kg = 1,100 mg/120 kg -> 1,100 mg/120 kg = 9.17 mg/kg Set Up an Equation to Find How Much is Administered PER DAY and Cancel Out "hr" 9.17 mg/6 hr • 24 hr/1 day -> 9.17 mg/6 • 24/1 day Multiply and Divide (9.17 • 24 mg)/6 day = 220.08 mg/6 day -> 220.08 mg/6 day = 36.7 mg/kg/day Is the Dose Safe? Yes. 36.7 mg/kg/day is less than the safe dose of 40 mg/kg/day.

Parenteral Medication Dosage Calculation A health care provider prescribes cefazolin (Ancef) 0.4253 g IM bid; Reconstitution instructions: For IM solution add 1.25 mL of diluent. Shake to dissolve. Provides an approximate volume of 1.6 mL (240 mg/mL) How many mL will you give? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 mL/240 mg • 1,000 mg/1 g -> 1 mL/240 • 1,000/1 g Based on the Information Provided in the Question, Cancel Out "g" 1 mL/240 • 1,000/1 g • 0.4253 g/1 -> 1 mL/240 • 1,000/1 • 0.4253/1 Multiply and Divide (1,000 • 0.4253 mL)/240 = 425.3 mL/240 -> 425.3 mL/240 = 1.77 mL Round to the Nearest Tenth 1.77 mL -> 1.8 mL

Parenteral Medication Dosage Calculation The recommended IV dose of gentamicin (Garamycin) is 1 to 5 mg/kg. What is a safe range to administer to an adult man weighing 190 pounds?

Set Up an Equation to Find the Highest Possible Safe Dose and, Using Conversions, Cancel Out "kg" 5 mg/1 kg • 1 kg/2.2 lbs -> 5 mg/1 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 5 mg/1 • 1/2.2 lbs • 190 lbs/1 -> 5 mg/1 • 1/2.2 lbs • 190/1 Multiply and Divide (5 • 190 mg)/2.2 = 950 mg/2.2 -> 950 mg/2.2 = 431.8 mg Set Up an Equation to Find the Lowest Possible Safe Dose and, Using Conversions, Cancel Out "kg" 1 mg/1 kg • 1 kg/2.2 lbs -> 1 mg/1 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 1 mg/1 • 1/2.2 lbs • 190 lbs/1 -> 1 mg/1 • 1/2.2 • 190/1 Multiply and Divide 190 mg/2.2 = 86.4 mg What is the Safe Dosage Range? 86 to 431 mg

Metric Conversions Convert 33.01 kg to g

Using "King Henry Drinks Ucky Dark Chocolate Milk" 33.01 kg to g -> kg = "King" Move from "King" (kg) to "Ucky" (g) 1 Place to the Right: Henry -> 2 Places to the Right: Drink -> 3 Places to the Right: Ucky Move the Decimal 3 Places to the Right 33.01 kg -> 33010 g

Household/U.S. Volume Conversions If Sarah drinks 80 ounces of water per day, how many gallons does she have per week?

Set Up an Equation 80 fl oz/1 day = x gal/y week Using Conversions, Cancel Out "fl oz" 8 fl oz = 1 cup (C) -> 80 fl oz/1 day • 1 C/8 fl oz = x gal/y week -> 80/1 day • 1 C/8 = x gal/y week Using Conversions, Cancel Out "C" 2 cups (C) = 1 pint (pt) -> 80/1 day • 1 C/8 • 1 pt/2 C = x gal/y week -> 80/1 day • 1/8 • 1 pt/2 = x gal/y week Using Conversions, Cancel Out "pt" 2 pints (pt) = 1 quart (qt) -> 80/1 day • 1/8 • 1 pt/2 • 1 qt/2 pt = x gal/y week -> 80/1 day • 1/8 • 1/2 • 1 qt/2 = x gal/y week Using Conversions, Cancel Out "qt" 4 Quarts (qt) = 1 Gallon (gal) -> 80/1 day • 1/8 • 1/2 • 1 qt/2 • 1 gal/4 qt = x gal/y week -> 80/1 day • 1/8 • 1/2 • 1/2 • 1 gal/4 = x gal/y week Using Conversions, Cancel Out "day" 7 days = 1 week -> 80/1 day • 1/8 • 1/2 • 1/2 • 1 gal/4 • 7 days/1 week = x gal/y week -> 80/1 • 1/8 • 1/2 • 1/2 • 1 gal/4 • 7/1 week = x gal/y week Multiply 80/1 • 1/8 • 1/2 • 1/2 • 1 gal/4 • 7/1 week = x gal/y week -> (80 • 7 gal)/(8 • 2 • 2 • 4 week) -> 560 gal/128 week Simplify (If Applicable) 560 gal/128 week -> 560 ÷ 8; 128 ÷ 8 -> 70 gal/16 week Find How Many Gallons Sarah Drinks PER WEEK (1 Week) 70 gal/16 week -> 70 ÷ 16 = 4.375 gal/week

mg/kg/day Give Ceclor 30 mg/kg/day PO in 3 separate, equally divided doses to a patient weighing 77 pounds. The prepared 75 mL of Ceclor is labeled 125 mg/mL. How many mL would the nurse administer per dose?

Set Up an Equation and Cancel Out "kg" 1 kg = 2.2 lb -> 30 mg/1 kg • 1 kg/2.2 lb -> 30 mg/1 • 1/2.2 lb Based on the Information Provided in the Question, Cancel Out "mg" 30 mg/1 • 1/2.2 lb • 1 mL/125 mg -> 30/1 • 1/2.2 lb • 1 mL/125 Based on the Information Provided in the Question, Cancel Out "lb" 30/1 • 1/2.2 lb • 1 mL/125 • 77 lb/1 -> 30/1 • 1/2.2 • 1 mL/125 • 77/1 Multiply (30 • 77 mL)/(2.2 • 125) = 2310/275 mL Divide 2310 ÷ 275 mL = 8.4 mL Divide Again to Find How Many mL are Administered PER DOSE (NOT Per Day) 8.4 mL ÷ 3 doses = 2.8 mL/dose

Dosing Based on the Patient's Weight Order: 12 mg/kg/day divided in doses every 8 hours Child's Weight: 22 lbs Available: 200 mg/5 mL How many mL does the nurse administer per dose?

Set Up an Equation and Cancel Out "kg" 12 mg/1 kg • 1 kg/2.2 lbs -> 12 mg/1 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 12 mg/1 • 1/2.2 lbs • 22 lbs/1 -> 12 mg/1 • 1/2.2 • 22/1 Multiply (12 • 22 mg)/2.2 = 264/2.2 mg Divide 264 ÷ 2.2 mg = 120 mg Set Up an Equation to Find How Many mg Are Administered Per Dose and Cancel Out "hr" 120 mg/24 hr • 8 hr/1 -> 120 mg/24 • 8/1 Multiply (120 • 8 mg)/24 = 960/24 mg Divide 960/24 mg = 40 mg Set Up an Equation to Find How Many mL Are Administered Per Dose and Cancel Out "mg" 40 mg/1 • 5 mL/200 mg -> 40/1 • 5 mL/200 Multiply (40 • 5 mL)/200 = 200/200 mL Divide 200/200 mL = 1 mL/dose

Dosing Based on the Patient's Weight Patient's Weight: 150 lb. Order: 0.3 mL/kg of body weight How many mL should the patient get? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "lbs" 150 lbs • 1 kg/2.2 lbs -> 150 • 1 kg/2.2 Based on the Information Provided in the Question, Cancel Out "kg" 150 • 1 kg/2.2 • 0.3 mL/1 kg -> 150 • 1/2.2 • 0.3 mL/1 Multiply (150 • 0.3 mL)/2.2 = 45/2.2 mL Divide 45 ÷ 2.2 = 20.45 mL Round to the Nearest Tenth 20.45 mL -> 20.5 mL

Oral Medication Dosage Calculation A health care provider prescribes potassium chloride (Klotrix) 0.35 mEq/lb po dissolved in 6 oz of oj at 8am; Available: Klotrix 8 mEq/mL. How many mL of Klotrix will you add to the oj for a 20.5 kg patient? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "mEq" 0.35 mEq/1 lb • 1 mL/8 mEq -> 0.35/1 lb • 1 mL/8 Using Conversions, Cancel Out "lb" 0.35/1 lb • 1 mL/8 • 2.2 lb/1 kg -> 0.35/1 • 1 mL/8 • 2.2/1 kg Based on the Information Found in the Question, Cancel Out "kg" 0.35/1 • 1 mL/8 • 2.2/1 kg • 20.5 kg/1 -> 0.35/1 • 1 mL/8 • 2.2/1 • 20.5/1 Multiply and Divide (0.35 • 2.2 • 20.5 mL)/8 = 15.785/8 mL -> 15.785/8 mL = 1.97 mL Round to the Nearest Whole Number 1.97 mL -> 2 mL

IV Flow Rates Determine the drip rate in gtt/min for the following: Order: 1,000 mL NS to infuse in 8 hours Drop Factor: 15 gtt/mL

Set Up an Equation and Cancel Out "mL" 15 gtt/1 mL • 1,000 mL/8 hr -> 15 gtt/1 • 1,000/8 hr Using Conversions, Cancel Out "hr" 15 gtt/1 • 1,000/8 hr • 1 hr/60 min -> 15 gtt/1 • 1,000/8 • 1/60 min Multiply and Divide (15 • 1,000 gtt)/(8 • 60 min) = 15,000 gtt/480 min -> 15,000 gtt/480 min = 31.25 gtt/min Round to the Nearest Whole Number 31.25 gtt/min -> 31 gtt/min

Dosage Calculation You have on hand hydromorphone (Dilaudid) 4 mg/mL. You need to administer 0.015 mg/kg to a patient who weighs 150 pounds. How many milliliters should you administer? (Round to the nearest hundredth)

Set Up an Equation and Cancel Out "mg" 0.015 mg/1 kg • 1 mL/4 mg -> 0.015/1 kg • 1 mL/4 Using Conversions, Cancel Out "kg" 0.015/1 kg • 1 mL/4 • 1 kg/2.2 lbs -> 0.015/1 • 1 mL/4 • 1/2.2 lb Based on the Information Provided in the Question, Cancel Out "lb" 0.015/1 • 1 mL/4 • 1/2.2 lb • 150 lb/1 -> 0.015/1 • 1 mL/4 • 1/2.2 • 150/1 Multiply and Divide (0.015 • 150 mL)/(4 • 2.2) = 2.25/8.8 mL -> 2.25/8.8 mL = 0.2557 mL Round to the Nearest Hundredth 0.2557 mL -> 0.26 mL

Dosage Calculation A patient with heart failure has a daily order for digoxin (Lanoxin) 0.25 mg PO. Digoxin 0.125 mg tablets are available. How many tablet(s) should you give?

Set Up an Equation and Cancel Out "mg" 0.25 mg • 1 tab/0.125 mg -> 0.25 • 1 tab/0.125 Multiply and Divide (0.25 • 1 tab)/0.125 = 0.25 tab/0.125 -> 0.25 tab/0.125 = 2 tab

Oral Medication Dosage Calculation A health care provider orders megestrol (Megace) Oral Suspension 160 mg po bid; Directions for mixing: Add 100 mL of water and shake vigorously. Each 0.5 mL will contain 10.7 mg of megestrol. How many Tbsp of megestrol will you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 0.5 mL/10.7 mg • 160 mg/1 -> 0.5 mL/10.7 • 160/1 Using Conversions, Cancel Out "mL" 0.5 mL/10.7 • 160/1 • 1 Tbsp/15 mL -> 0.5/10.7 • 160/1 • 1 Tbsp/15 Multiply and Divide (0.5 • 160 Tbsp)/(10.7 • 15) = 80 Tbsp/160.5 -> 80 Tbsp/160.5 = 0.4984 Tbsp Round to the Nearest Tenth 0.4984 Tbsp -> 0.5 Tbsp

Oral Medication Dosage Calculation You have digoxin (Lanoxin) 0.25 mg tablets, and you need to administer 0.375 mg PO. How many tablet(s) should you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 tab/0.25 mg • 0.375 mg/1 -> 1 tab/0.25 • 0.375/1 Multiply and Divide 0.375 tab/0.25 = 1.5 tab

Oral Medication Dosage Calculation A patient is sent home on captopril (Capoten), 6.25 mg PO b.i.d. Her pharmacist dispenses 25 mg scored tablets. How many tablet(s) should the patient take for each dose? (Convert to a fraction, if necessary)

Set Up an Equation and Cancel Out "mg" 1 tab/25 mg • 6.25 mg/1 -> 1 tab/25 • 6.25/1 Multiply and Divide 6.25 tab/25 = 0.25 tab Convert to a Fraction 0.25 tab -> 25/100 tab Simplify 25/100 tab -> (25 ÷ 5)/(100 ÷ 5) tab -> 5/20 tab -> (5 ÷ 5)/(20 ÷ 5) tab -> 1/4 tab

Oral Medication Dosage Calculation Your patient is to receive metoprolol tartrate (Lopressor) 25 mg/day PO. The pharmacist dispenses 50 mg scored tablets. How many tablet(s) should your patient take each day?

Set Up an Equation and Cancel Out "mg" 1 tab/50 mg • 25 mg/1 -> 1 tab/50 • 25/1 Multiply and Divide 25 tab/50 = 0.5 tab

Oral Medication Dosage Calculation A health care provider prescribes hydroxyzine (Vistaril) Oral Susp 10 mg q 4 hr prn anxiety; Directions for mixing: Add 125 mL of water and shake well. Each tsp will yield 15 mg of Vistaril. How many mL will you give? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 1 tsp/15 mg • 10 mg/1 -> 1 tsp/15 • 10/1 Using Conversions, Cancel Out "tsp" 1 tsp/15 • 10/1 • 5 mL/1 tsp -> 1/15 • 10/1 • 5 mL/1 Multiply and Divide (10 • 5 mL)/15 = 50 mL/15 -> 50 mL/15 = 3.33 mL Round to the Nearest Tenth 3.33 mL -> 3.3 mL

Oral Medication Dosage Calculation A health care provider prescribed ondansetron (Zofran) 8 mg p.o. t.i.d.; Available: Zofran in a 100 mL bottle labeled 4 mg/tsp. How many mL will the nurse administer for each dose?

Set Up an Equation and Cancel Out "mg" 1 tsp/4 mg • 8 mg/1 -> 1 tsp/4 • 8/1 Using Conversions, Cancel Out "tsp" 1 tsp/4 • 8/1 • 5 mL/1 tsp -> 1/4 • 8/1 • 5 mL/1 Multiply and Divide (8 • 5 mL)/4 = 40 mL/4 -> 40 mL/4 = 10 mL

Parenteral Medication Dosage Calculation A health care provider prescribes meperidine (Demerol) 50 mg IVP q 6 hr prn pain. Available on hand is meperidine 75 mg/1.3 mL. How many mL will you administer? (Round to the nearest hundredth)

Set Up an Equation and Cancel Out "mg" 1.3 mL/75 mg • 50 mg/1 -> 1.3 mL/75 • 50/1 Multiply and Divide (1.3 • 50 mL)/75 = 65/75 mL -> 65/75 mL = 0.867 mL Round to the Nearest Hundredth 0.867 mL -> 0.87 mL

Oral Medication Dosage Calculation A health care provider prescribed Diuril 1.8 mg/kg PO t.i.d.; Available: Diuril 12.5 mg caps. How many cap(s) will you administer for each dose to a 31 lb child? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "mg" 1.8 mg/1 kg • 1 cap/12.5 mg -> 1.8/1 kg • 1 cap/12.5 Using Conversions, Cancel Out "kg" 1.8/1 kg • 1 cap/12.5 • 1 kg/2.2 lbs -> 1.8/1 • 1 cap/12.5 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 1.8/1 • 1 cap/12.5 • 1/2.2 lbs • 31 lbs/1 -> 1.8/1 • 1 cap/12.5 • 1/2.2 • 31/1 Multiply and Divide (1.8 • 31 cap)/(12.5 • 2.2) = 55.8/27.5 cap -> 55.8/27.5 cap = 2.03 cap Round to the Nearest Whole Number 2.03 cap -> 2 cap

Dosage Calculation A 12-year-old child was admitted to the emergency department because of an asthma attack. Upon assessment, you found out that the child's weight measures 82.4 lbs. The primary care provider ordered 2 mg/kg of methylprednisolone (Solu-Medrol.) The available stock dose is 125 mg/2 mL. How many mL will the nurse administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 2 mg/1 kg • 2 mL/125 mg -> 2/1 kg • 2 mL/125 Using Conversions, Cancel Out "kg" 2/1 kg • 2 mL/125 • 1 kg/2.2 lb -> 2/1 • 2 mL/125 • 1/2.2 lb Based on the Information Provided in the Question, Cancel Out "lb" 2/1 • 2 mL/125 • 1/2.2 lb • 82.4 lb/1 -> 2/1 • 2 mL/125 • 1/2.2 • 82.4/1 Multiply and Divide (2 • 2 mL • 82.4)/(125 • 2.2) = 329.6 mL/275 -> 329.6 mL/275 = 1.198 mL Round to the Nearest Tenth 1.198 mL -> 1.2 mL

Dosage Calculation A primary healthcare provider ordered ceftriaxone (Rocephin) for a 4-year-old child with lower respiratory tract infection. The dose required is 20 mg/kg/day divided twice a day, administer per dose via IV. The child's weight is 29 lbs. The drug comes prediluted in a concentration of 10 mg/mL. How much of the medication will you administer in mL? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 20 mg/1 kg • 1 mL/10 mg -> 20/1 kg • 1 mL/10 Using Conversions, Cancel Out "kg" 20/1 kg • 1 mL/10 • 1 kg/2.2 lbs -> 20/1 • 1 mL/10 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 20/1 • 1 mL/10 • 1/2.2 lbs • 29 lbs/1 -> 20/1 • 1 mL/10 • 1/2.2 • 29/1 Multiply and Divide (20 • 29 mL)/(10 • 2.2) = 580/22 mL -> 580/22 mL = 26.36 mL Set Up an Equation to Find How Much Medication Will Be Administered PER DOSE and Cancel Out "day" 26.36 mL/1 day • 1 day/2 doses -> 26.36 mL/1 • 1/2 doses Multiply and Divide 26.36 mL/2 doses = 13.18 mL/dose Round to the Nearest Tenth 13.18 mL -> 13.2 mL

Oral Medication Dosage Calculation A health care provider orders cefaclor (Ceclor) 45 mg/kg/day p.o. in 3 divided doses for a patient who weighs 66 pounds. A 75 mL stock medication is labeled Ceclor 125 mg/mL. How many mL would the nurse administer per dose? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 45 mg/1 kg • 1 mL/125 mg -> 45/1 kg • 1 mL/125 Using Conversions, Cancel Out "kg" 45/1 kg • 1 mL/125 • 1 kg/2.2 lbs -> 45/1 • 1 mL/125 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 45/1 • 1 mL/125 • 1/2.2 lbs • 66 lbs/1 -> 45/1 • 1 mL/125 • 1/2.2 • 66/1 Multiply and Divide (45 • 66 mL)/(125 • 2.2) = 2970/275 mL -> 2970/275 mL = 10.8 mL Set Up an Equation to Find How Many mL Would Be Administered PER DOSE and Cancel Out "day" 10.8 mL/1 day • 1 day/3 doses -> 10.8 mL/1 • 1/3 doses Multiply and Divide 10.8 mL/3 = 3.6 mL

Oral Medication Dosage Calculation Your patient has headache, but has difficulty swallowing pills. The physician orders acetaminophen (Tylenol) 1,000 mg PO every 4 to 6 hours prn. You have acetaminophen elixir 160 mg in 5 mL. How much will you administer in mL? (Round to the nearest hundredth)

Set Up an Equation and Cancel Out "mg" 5 mL/160 mg • 1,000 mg/1 -> 5 mL/160 • 1,000/1 Multiply and Divide (5 • 1,000 mL)/160 = 5,000/160 mL -> 5,000/160 mL = 31.25 mL

Weight Based Calculations A child that weighs 20 pounds has been prescribed liquid Tylenol at 10 mg/kg/dose po. Tylenol is available at 160 mg/5 mL. How many mL of Tylenol will the nurse administer?

Set Up an Equation and Cancel Out "mg" 5 mL/160 mg • 10 mg/1 kg -> 5 mL/160 • 10/1 kg Using Conversions, Cancel out "kg" 5 mL/160 • 10/1 kg • 1 kg/2.2 lbs -> 5 mL/160 • 10/1 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 5 mL/160 • 10/1 • 1/2.2 lbs • 20 lbs/1 -> 5 mL/160 • 10/1 • 1/2.2 • 20/1 Multiply and Divide (5 • 10 • 20 mL)/(160 • 2.2) = 1,000 mL/352 -> 1,000 mL/352 = 2.8 mL

Oral Medication Dosage Calculation You have an order for phenobarbital (Luminal) 50 mg PO at bedtime. It is supplied as phenobarbital elixir 20 mg/5 mL. How much in mL will you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 5 mL/20 mg • 50 mg/1 -> 5 mL/20 • 50/1 Multiply and Divide (5 • 50 mL)/20 = 250/20 mL -> 250/20 mL = 12.5 mL

Oral Medication Dosage Calculation A health care provider prescribes ceftazidime (Fortaz) mg/kg/day p.o. 50 mg/kg p.o. t.i.d. to a child who weighs 25.5 kg. Fortaz is available in an oral suspension labeled 100 mg/mL. How many mL would the nurse administer per dose? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 50 mg/1 kg • 1 mL/100 mg -> 50/1 kg • 1 mL/100 Based on the Information Provided in the Question, Cancel Out "kg" 50/1 kg • 1 mL/100 • 25.5 kg -> 50/1 • 1 mL/100 • 25.5 Multiply and Divide (50 • 25.5 mL)/100 = 1,275 mL/100 -> 1,275/100 mL = 12.75 mL Round to the Nearest Tenth 12.75 mL -> 12.8 mL

Dosage Calculation A health care provider orders amoxicillin syrup to a 3-year-old child with a UTI. Your assessment reveals the following data: Temperature: 38.5º C Heart Rate: 88 bpm Respiratory Rate: 30 bpm Blood Pressure: 90/50 Height: 98 cm Weight: 12 kg (26.4 lbs) The dosage required as per order is 50 mg/kg/day divided into 3 doses per day (TID.) Available stock is a suspension with a concentration of 400 mg/5 mL. How much will you administer per dose? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "mg" 50 mg/1 kg • 5 mL/400 mg -> 50/1 kg • 5 mL/400 Based on the information Provided in the Question, Cancel Out "kg" 50/1 kg • 5 mL/400 • 12 kg/1 -> 50/1 • 5 mL/400 • 12/1 Multiply and Divide (50 • 5 mL• 12)/400 = 3,000/400 mL -> 3,000/400 mL = 7.5 mL Set Up an Equation to Find How Much to Administer PER DOSE and Cancel Out "day" 7.5 mL/1 day • 1 day/3 doses -> 7.5 mL/1 • 1/3 doses Multiply and Divide 7.5 mL/3 doses = 2.5 mL/dose

Oral Medication Dosage Calculation A nurse practitioner prescribed clindamycin (Cleocin) Oral Susp 600 mg po qid; Directions for mixing: Add 100 mL of water and shake vigorously. Each 2.5 mL will contain 100 mg of Cleocin. How many tsp of Cleocin will you administer? (Round to the nearest whole number)

Set Up an Equation and Cancel Out "mg" 600 mg/1 • 2.5 mL/100 mg -> 600/1 • 2.5 mL/100 Using Conversions, Cancel Out "mL" 600/1 • 2.5 mL/100 • 1 tsp/5 mL -> 600/1 • 2.5/100 • 1 tsp/5 Multiply and Divide (600 • 2.5 tsp)/(100 • 5) = 1,500 tsp/500 -> 1,500 tsp/500 = 3 tsp

Oral Medication Dosage Calculation A patient is taking acetaminophen (Tylenol) 325 mg, 2 tablets PO every 6 hours. How many gram(s) is the patient receiving in 24 hours? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "tab" 325 mg/1 tab • 2 tab/6 hr -> 325 mg/1 • 2/6 hr Using Conversions, Cancel Out "mg" 325 mg/1 • 2/6 hr • 1 g/1,000 mg -> 325/1 • 2/6 hr • 1 g/1,000 Based on the Information Provided in the Question, Cancel Out "hr" 325/1 • 2/6 hr • 1 g/1,000 • 24 hr/1 -> 325/1 • 2/6 • 1 g/1,000 • 24/1 Multiply and Divide (325 • 2 • 24 g)/(6 • 1,000) = 15,600 g/6,000 -> 15,600 g/6,000 = 2.6 g

Parenteral Medication Dosage Calculation A health care provider orders Penicillin G 223,500 units IM q 4 hr; Available: Penicillin G 500,000 units/2.5 mL. How many mL will you administer? (Round to the nearest tenth)

Set Up an Equation and Cancel Out "units" 2.5 mL/500,000 units • 223,500 units/1 -> 2.5 mL/500,000 • 223,500/1 Multiply and Divide (2.5 • 223,500 mL)/500,000 = 558,750 mL/500,000 -> 558,750 mL/500,000 = 1.12 mL Round to the Nearest Tenth 1.12 mL -> 1.1 mL

IV Flow Rates Determine the flow rate in mL/hr The order is for 1,200 units of Heparin per hr IV The pharmacy has Heparin, 25,000 units in 200 mL NS

Set Up an Equation and Cancel Out "units" 200 mL/25,000 units • 1,200 units/1 hr -> 200 mL/25,000 • 1,200/1 hr Multiply and Divide (200 • 1,200 mL)/25,000 hr = 240,000 mL/25,000 hr -> 240,000 mL/25,000 hr = 9.6 mL/hr

Oral Medication Dosage Calculation A homebound patient must take 400,000 units of nystatin PO every 4 hours, to swish in the mouth, and then swallow. It is available as 100,000 units/5 mL. The patient only has household measuring spoons. How should the patient be instructed to take the dose in tsp?

Set Up an Equation and Cancel Out "units" 5 mL/100,000 units • 400,000 units -> 5 mL/100,000 • 400,000 Using Conversions, Cancel Out "mL" 5 mL/100,000 • 400,000 • 1 tsp/5 mL -> 5/100,000 • 400,000 • 1 tsp/5 Multiply and Divide (5 • 400,000 tsp)/(100,000 • 5) = 2,000,000 tsp/500,000 -> 2,000,000 tsp/500,000 = 4 tsp

Weight Based Calculations A child that weighs 20 kg has been prescribed Tobradex at 5 mg/kg/dose q8h. Available is Tobradex 80 mg/2 mL. #1: How many milliliters would the nurse administer per dose? #2: How many mL would the nurse administer per day?

Set Up an Equation and Cancel out "mg" 2 mL/80 mg • 5 mg/1 kg -> 2 mL/80 • 5/1 kg Based on the Information Provided in the Question, Cancel Out "kg" 2 mL/80 • 5/1 kg • 20 kg/1 -> 2 mL/80 • 5/1 • 20/1 Multiply and Divide (2 • 5 • 20 mL)/80 = 200 mL/80 -> 200 mL/80 = #1: 2.5 mL Set Up an Equation to Find How Many mL are Administered PER DAY and Cancel Out "hr" 2.5 mL/8 hr • 24 hr/1 day -> 2.5 mL/8 • 24/1 day Multiply and Divide (2.5 mL • 24)/8 day = 60 mL/8 day -> 60 mL/8 day = #2: 7.5 mL/day

Parenteral Medication Dosage Calculation A health care provider orders tobramycin 1.25 mg/kg IM q 12 hr. Available on hand is tobramycin 0.2 g/mL. How many mL will you administer to a 183 lbs patient for each dose? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "g" 1 mL/0.2 g • 1 g/1,000 mg -> 1 mL/0.2 • 1/1,000 mg Based on the Information Provided in the Question, Cancel Out "mg" 1 mL/0.2 • 1/1,000 mg • 1.25 mg/1 kg -> 1 mL/0.2 • 1/1,000 • 1.25/1 kg Using Conversions, Cancel Out "kg" 1 mL/0.2 • 1/1,000 • 1.25/1 kg • 1 kg/2.2 lbs -> 1 mL/0.2 • 1/1,000 • 1.25/1 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 1 mL/0.2 • 1/1,000 • 1.25/1 • 1/2.2 lbs • 183 lbs/1 -> 1 mL/0.2 • 1/1,000 • 1.25/1 • 1/2.2 • 183/1 Multiply and Divide (1.25 • 183 mL)/(0.2 • 1,000 • 2.2) = 228.75 mL/440 -> 228.75 mL/440 = 0.52 mL Round to the Nearest Tenth 0.52 mL -> 0.5 mL

Parenteral Medication Dosage Calculation A health care provider prescribed kanamycin (Kantrex) 7.5 mg/kg IM q 12 hr; Available: kanamycin 0.35 g/mL. How many mL will you administer for each dose to a 157 lb patient? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "g" 1 mL/0.35 g • 1 g/1,000 mg -> 1 mL/0.35 • 1/1,000 mg Based on the Information Provided in the Question, Cancel Out "mg" 1 mL/0.35 • 1/1,000 mg • 7.5 mg/1 kg -> 1 mL/0.35 • 1/1,000 • 7.5/1 kg Using Conversions, Cancel Out "kg" 1 mL/0.35 • 1/1,000 • 7.5/1 kg • 1 kg/2.2 lbs -> 1 mL/0.35 • 1/1,000 • 7.5/1 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 1 mL/0.35 • 1/1,000 • 7.5/1 • 1/2.2 lbs • 157 lbs/1 -> 1 mL/0.35 • 1/1,000 • 7.5/1 • 1/2.2 • 157/1 Multiply and Divide (7.5 • 157 mL)/(0.35 • 1,000 • 2.2) = 1,177.5 mL/770 -> 1,177.5 mL/770 = 1.53 mL Round to the Nearest Tenth 1.53 mL -> 1.5 mL

Oral Medication Dosage Calculation A health care provider prescribes nafcillin (Nafcil) 500 mg po pc; Available on hand is nafcillin 1 g tab (scored.) How many tab(s) will you administer per day? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "g" 1 tab/1 g • 1 g/1,000 mg -> 1 tab/1 • 1/1,000 mg Based on the Information Provided in the Question, Cancel Out "mg" 1 tab/1 • 1/1,000 mg • 500 mg -> 1 tab/1 • 1/1,000 • 500 Multiply and Divide 500 tab/1,000 = 0.5 tab Set Up an Equation to Find How Many tab(s) Are Administered Per Day (After Each Meal) and Cancel Out "meal" 0.5 tab/1 meal • 3 meals/1 day -> 0.5 tab/1 • 3/1 day Multiply and Divide (0.5 • 3 tab)/day = 1.5 tab/day

Parenteral Medication Dosage Calculation A health care provider orders amikacin (Amikin) 5 mg/lb IM q 12 hr; Available: Amikacin 0.9 g/2 mL. How many mL will you administer to a 72.7 kg patient? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "g" 2 mL/0.9 g • 1 g/1,000 mg -> 2 mL/0.9 • 1/1,000 mg Based on the Information Provided in the Question, Cancel out "mg" 2 mL/0.9 • 1/1,000 mg • 5 mg/1 lb -> 2 mL/0.9 • 1/1,000 • 5/1 lb Using Conversions, Cancel Out "lb" 2 mL/0.9 • 1/1,000 • 5/1 lb • 2.2 lb/1 kg -> 2 mL/0.9 • 1/1,000 • 5/1 • 2.2/1 kg Based on the Information Provided in the Question, Cancel Out "kg" 2 mL/0.9 • 1/1,000 • 5/1 • 2.2/1 kg • 72.7 kg/1 -> 2 mL/0.9 • 1/1,000 • 5/1 • 2.2/1 • 72.7/1 Multiply and Divide (2 • 5 • 2.2 • 72.7 mL)/(0.9 • 1,000) = 1599.4 mL/900 -> 1599.4 mL/900 = 1.78 mL Round to the Nearest Tenth 1.78 mL -> 1.8 mL

Parenteral Medication Dosage Calculation A health care provider orders Streptomycin 1.75 mg/lb IM q 12 hr; Available: Streptomycin 0.35 g/2.3 mL. How many mL will you administer a day to a 59 kg patient? (Round to the nearest whole number)

Set Up an Equation and, Using Conversions, Cancel Out "g" 2.3 mL/0.35 g • 1 g/1,000 mg -> 2.3 mL/0.35 • 1/1,000 mg Based on the Information Provided in the Question, Cancel Out "mg" 2.3 mL/0.35 • 1/1,000 mg • 1.75 mg/1 lb -> 2.3 mL/0.35 • 1/1,000 • 1.75/1 lb Using Conversions, Cancel Out "lb" 2.3 mL/0.35 • 1/1,000 • 1.75/1 lb • 2.2 lb/1 kg -> 2.3 mL/0.35 • 1/1,000 • 1.75/1 • 2.2/1 kg Based on the Information Provided in the Question, Cancel Out "kg" 2.3 mL/0.35 • 1/1,000 • 1.75/1 • 2.2/1 kg • 59 kg/1 -> 2.3 mL/0.35 • 1/1,000 • 1.75/1 • 2.2/1 • 59/1 Multiply and Divide (2.3 • 1.75 • 2.2 • 59 mL)/(0.35 • 1,000) = 522.445 mL/350 -> 522.445 mL/350 = 1.4927 mL Set Up an Equation to Find How Many mL Will Be Administered PER DAY and Cancel Out "hr" 1.4927 mL/12 hr • 24 hr/1 day -> 1.4927 mL/12 • 24/1 day Multiply and Divide (1.4927 • 24 mL)/12 day = 35.8248 mL/12 day -> 35.8248 mL/12 day = 2.9854 mL Round to the Nearest Whole Number 2.9854 mL -> 3 mL

Oral Medication Dosage Calculation You have an order for levothyroxine (Synthroid) 0.05 mg PO. You have on hand Synthroid 100 mcg tablets. How many tablets should you administer? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "mcg" 1 tab/100 mcg • 1,000 mcg/1 mg -> 1 tab/100 • 1,000/1 mg Based on the Information Provided in the Question, Cancel Out "mg" 1 tab/100 • 1,000/1 mg • 0.05 mg/1 -> 1 tab/100 • 1,000/1 • 0.05/1 Multiply and Divide (1,000 • 0.05 tab)/100 = 50 tab/100 -> 50 tab/100 = 0.5 tab

Dosage Calculation A patient with ventricular fibrillation is prescribed with bretylium 5 mcg/kg/min. The medication comes mixed 50 mg in 50 mL of 0.9% normal saline. The patient's weight is 170 lbs. How much of the medication will you administer per hour? (Round to the nearest whole number)

Set Up an Equation and, Using Conversions, Cancel Out "mcg" 5 mcg/1 kg • 1 mg/1,000 mcg -> 5/1 kg • 1 mg/1,000 Based on the Information Provided in the Question, Cancel Out "mg" 5/1 kg • 1 mg/1,000 • 50 mL/50 mg -> 5/1 kg • 1/1,000 • 50 mL/50 Using Conversions, Cancel Out "kg" 5/1 kg • 1/1,000 • 50 mL/50 • 1 kg/2.2 lb -> 5/1 • 1/1,000 • 50 mL/50 • 1/2.2 lbs Based on the Information Provided in the Question, Cancel Out "lbs" 5/1 • 1/1,000 • 50 mL/50 • 1/2.2 lbs • 170 lbs/1 -> 5/1 • 1/1,000 • 50 mL/50 • 1/2.2 • 170/1 Multiply and Divide (5 • 50 mL • 170)/(1,000 • 50 • 2.2) = 42,500 mL/110,000 -> 42,500 mL/110,000 = 0.39 mL Set Up an Equation to Find How Much of the Medication Will Be Administered PER HOUR and Cancel Out "min" 0.39 mL/1 min • 60 min/1 hr -> 0.39 mL/1 • 60/1 hr Multiply and Divide (0.39 mL • 60)/1 hr = 23.4 mL/hr Round to the Nearest Whole Number 23.4 mL/hr -> 23 mL/hr

Oral Medication Dosage Calculation A health care provider prescribed phenytoin (Dilantin) 0.75 g PO stat; Available: Dilantin 250 mg cap. How many cap(s) will you administer?

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 cap/250 mg • 1,000 mg/1 g -> 1 cap/250 • 1,000/1 g Based on the Information Provided in the Question, Cancel Out "g" 1 cap/250 • 1,000/1 g • 0.75 g/1 -> 1 cap/250 • 1,000/1 • 0.75/1 Multiply and Divide (1,000 • 0.75 cap)/250 = 750 cap/250 -> 750 cap/250 = 3 cap

Parenteral Medication Dosage Calculation A health care provider orders ceftazidime (Tazidime) 0.3 g IM tid; Reconstitution instructions: For IM solution add 1.5 mL of diluent. Shake to dissolve. Provides an approximate volume of 1.8 mL (280 mg/mL) How many mL will you give? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 mL/280 mg • 1,000 mg/1 g -> 1 mL/280 • 1,000/1 g Based on the Information Provided in the Question, Cancel Out "g" 1 mL/280 • 1,000/1 g • 0.3 g/1 -> 1 mL/280 • 1,000/1 • 0.3/1 Multiply and Divide (1,000 • 0.3 mL)/280 = 300 mL/280 -> 300 mL/280 = 1.07 mL Round to the Nearest Tenth 1.07 mL -> 1.1 mL

Oral Medication Dosage Calculation A health care provider orders acetaminophen (Tylenol) supp. 1 g pr q 6 hr prn temp is greater than 101. Available: Tylenol supp. 325 mg (scored) How many supp. will you administer? (Round to the Nearest Whole Number)

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 supp./325 mg. • 1,000 mg/1 g -> 1 supp./325 • 1,000/1 g Based on the Information Provided in the Question, Cancel Out "g" 1 supp./325 • 1,000/1 g • 1 g -> 1 supp./325 • 1,000/1 • 1 Multiply and Divide 1,000 supp./325 = 3.08 supp. Round to the Nearest Whole Number 3.08 supp. -> 3 supp.

Oral Medication Dosage Calculation Levothyroxine (Synthroid) 150 mcg PO per day is ordered for a patient with hypothyroidism. It is supplied as 0.075 mg tablets. A safe dose of Synthroid is 1.5 mcg/kg/day. The patient weighs 196 pounds. #1: How many tablets should the patient take daily? #2: Is the dose safe?

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 tab/0.075 mg • 1 mg/1,000 mcg -> 1 tab/0.075 • 1/1,000 mcg Based on the Information Provided in the Question, Cancel Out "mcg" 1 tab/0.075 • 1/1,000 mcg • 150 mcg -> 1 tab/0.075 • 1/1,000 • 150 Multiply and Divide 150 tab/(0.075 • 1,000) = 150 tab/75 -> 150 tab/75 = #1: 2 tab Set Up a Second Equation to Find if the Dose is Safe and, Using Conversions, Cancel Out "lbs" 150 mcg/196 lbs • 2.2 lbs/1 kg -> 150 mcg/196 • 2.2/1 kg Multiply and Divide (150 • 2.2 mcg)/196 kg = 330 mcg/196 kg -> 330 mcg/196 kg = 1.68 mcg/kg Is the Dose Safe? #2: No, the dose is not safe because 1.68 mcg/kg is greater than 1.5 mcg/kg

Oral Medication Dosage Calculation A health care provider order prazosin HCI (Minipress) 3,000 micrograms PO ac; Available: Minipress tabs 2 mg (scored.) How many tab(s) will you administer in 24 hr? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 tab/2 mg • 1 mg/1,000 mcg -> 1 tab/2 • 1/1,000 mcg Based on the Information Provided in the Question, Cancel Out "mcg" 1 tab/2 • 1/1,000 mcg • 3,000 mcg/1 -> 1 tab/2 • 1/1,000 • 3,000/1 Multiply and Divide 3,000 tab/(2 • 1,000) = 3,000 tab/2,000 -> 3,000 tab/2,000 = 1.5 tab Set Up an Equation to Find How Many Tablets Are Administered in 24 Hours and Cancel Out "meal" 1.5 tab/1 meal • 3 meal/1 day -> 1.5 tab/1 • 3/1 day Multiply 1.5 tab • 3/1 day = 4.5 tabs

Metric Conversions Convert 2.3 L to mL

Using "King Henry Drinks Ucky Dark Chocolate Milk" 2.3 L to mL -> L = "Ucky" Move From "Ucky" (L) to "Milk" (mL) 1 Place to the Right: Dark -> 2 Places to the Right: Chocolate -> 3 Places to the Right: Milk Move the Decimal 3 Places to the Right (Fill in Empty Spaces with 0) 2.3 L -> 2,300 mL

Household/U.S. Volume Conversions Ms. Gal

• 1 Gallon = 4 Quarts • 1 Quart = 2 Pints • 1 Pint = 2 Cups • 1 Cup = 8 Fluid Ounces Therefore... • 1 Gallon = 8 Pints • 1 Gallon = 16 Cups • 1 Gallon = 128 Fluid Ounces

Oral Medication Dosage Calculation Your order reads cortisone (Cortone Acetate) 15 mg PO every morning. You have on hand cortisone 10 mg tablets. How many tablet(s) will you administer? (Round to the nearest tenth)

Set Up and Equation and Cancel Out "mg" 1 tab/10 mg • 15 mg/1 -> 1 tab/10 • 15/1 Multiply and Divide 15 tab/10 = 1.5 tab

Metric Conversions "King Henry Drinks Ucky Dark Chocolate Milk"

"King" = Kilo • kL (Volume) • kg (Weight/Mass) • km (Length) "Henry" = Hecto • hL (Volume) • hg (Weight/Mass) • hm (Length) "Drinks" = Deca • daL (Volume) • dag (Weight/Mass) • dam (Length) "Ucky" = Unit • L (Liter; Volume) • g (Gram; Weight/Mass) • m (Meter; Length) "Dark" = Deci • dL (Volume) • dg (Weight/Mass) • dm (Length) "Chocolate" = Centi • cL (Volume) • cg (Weight/Mass) • cm (Length) "Milk" = Milli • mL (Volume) • mg (Weight/Mass) • mm (Length)

Oral Medication Dosage Calculation You are caring for your ill grandmother at home. She has an order for magnesium hydroxide/aluminum hydroxide (Maalox) 10 mL PO prn stomach upset. How do you instruct her to measure her dose in tsp using household measuring spoons?

Set Up an Equation and, Using Conversions, Cancel Out "mL" 10 mL/1 • 1 tsp/5 mL -> 10/1 • 1 tsp/5 Multiply and Divide 10 tsp/5 = 2 tsp

Infusion Pumps Order: A Heparin drip is infusing at 40 mL/hr Available/Drug Label: Heparin 20,000 units in 500 mL of D5W At this rate, how many units of Heparin are being delivered per hour?

Approach #1 Divide 20,000 units/500 mL = 40 units/mL Multiply 40 units/mL • 40 mL/hr = 1,600 units/hr Approach #2 Set Up an Equation 20,000 units/500 mL • 40 mL/1 hr Cancel Out "mL" 20,000 units/500 mL • 40 mL/1 hr -> 20,000 units/500 • 40/1 hr Multiply (20,000 • 40 units)/500 hr = 800,000 units/500 hr Divide 800,000 units ÷ 500 hr = 1,600 units/hr

Dimensional Analysis Introduction How many pounds are in 44 ounces?

Remember Your Conversion: 1 pound = 16 ounces Set Up an Equation and Cancel Out "oz": (44 oz/1) • (1 lb/16 oz) -> (44 oz/1) • (1 lb/16 oz) -> (44/1) • (1 lb/16) Multiply: (44 • 1 lb)/(1 • 16) -> 44/16 lbs Divide (If Applicable): 44 ÷ 16 = 2.75 lbs.

Parenteral Medication Dosage Calculation A patient with complaints of chest pain is ordered to receive diltiazem (Cardizem) 5 mg IVP. The vial contains 10 mg/2 mL. How many mL will you give?

Set Up an Equation and Cancel Out "mg" 2 mL/10 mg • 5 mg/1 -> 2 mL/10 • 5/1 Multiply and Divide (2 • 5 mL)/10 = 10 mL/10 -> 10 mL/10 = 1 mL

Parenteral Medication Dosage Calculation A health care provider prescribed bumetanide (Bumex) 0.8 mg IV bolus bid; Reconstitution instructions: Constitute to 1,000 micrograms/3.1 mL with 4.8 mL of 5% Dextrose Water for Injection. How many mL will you administer? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "mcg" 3.1 mL/1,000 mcg • 1,000 mcg/1 mg -> 3.1 mL/1,000 • 1,000/1 mg Based on the Information Provided in the Question, Cancel Out "mg" 3.1 mL/1,000 • 1,000/1 mg • 0.8 mg/1 -> 3.1 mL/1,000 • 1,000/1 • 0.8/1 Multiply and Divide (3.1 • 1,000 • 0.8 mL)/1,000 = 2,480 mL/1,000 -> 2,480 mL/1,000 = 2.48 mL Round to the Nearest Tenth 2.48 mL -> 2.5 mL

Oral Liquids A patient has been prescribed Amoxicillin 0.75 g po qid. The pharmacy supplies Amoxicillin on hand at 125 mg/tsp. #1: How many tsp would the nurse administer per dose? #2: How many tsp would the nurse administer per day? #3 How many mL would the nurse administer per dose?

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 tsp/125 mg • 1,000 mg/1 g -> 1 tsp/125 • 1,000/1 g Based on the Information Provided in the Question, Cancel Out "g" 1 tsp/125 • 1,000/1 g • 0.75 g/1 -> 1 tsp/125 • 1,000/1 • 0.75/1 dose Multiply and Divide (1,000 • 0.75 tsp)/125 dose = 750 tsp/125 dose -> 750 tsp/125 dose = #1: 6 tsp/dose Set Up an Equation to Find How Many tsp are Administered PER DAY and Cancel Out "dose" 6 tsp/1 dose • 4 dose/1 day -> 6 tsp/1 • 4/1 day Multiply and Divide (6 tsp • 4)/1 day = #2: 24 tsp/day Set Up an Equation to Find How Many mL are Administered PER DOSE and, Using Conversions, Cancel Out "tsp" 6 tsp/1 dose • 5 mL/1 tsp -> 6/1 dose • 5 mL/1 Multiply and Divide (6 • 5 mL)/1 dose = #3: 30 mL/dose

Parenteral Medication Dosage Calculation Lanoxin (digoxin) 125 mcg is ordered IVP every a.m. The vial contains 0.5 mg in 2 mL. How many mL will you give? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "mg" 2 mL/0.5 mg • 1 mg/1,000 mcg -> 2 mL/0.5 • 1/1,000 mcg Based on the Information Provided in the Question, Cancel Out "mcg" 2 mL/0.5 • 1/1,000 mcg • 125 mcg/1 -> 2 mL/0.5 • 1/1,000 • 125/1 Multiply and Divide (2 • 125 mL)/(0.5 • 1,000) = 250 mL/500 -> 250 mL/500 = 0.5 mL

Oral Medication Dosage Calculation A health care provider ordered sulfasalazine (Azulfidine) Oral Susp 500 mg q 6 hr; Directions for mixing: Add 125 mL of water and shake well. Each tbsp will yield 1.5 g of sulfasalazine. How many mL will you give?

Set Up an Equation and, Using Conversions, Cancel Out "mg" 500 mg • 1 g/1,000 mg -> 500 • 1 g/1,000 Based on the Information Provided in the Question, Cancel Out "g" 500 • 1 g/1,000 • 1 Tbsp/1.5 g -> 500 • 1/1,000 • 1 Tbsp/1.5 Using Conversions, Cancel Out "Tbsp" 500 • 1/1,000 • 1 Tbsp/1.5 • 15 mL/1 Tbsp -> 500 • 1/1,000 • 1/1.5 • 15 mL/1 Multiply and Divide (500 • 15 mL)/(1,000 • 1.5) = 7,500 mL/1,500 -> 7,500 mL/1,500 = 5 mL

Oral Medication Dosage Calculation A health care provider prescribes Synthroid 75 mcg PO daily; Available: Synthroid 0.15 mg tab (scored.) How many tab(s) will you administer? (Round to the nearest tenth)

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 tab/0.15 mg • 1 mg/1,000 mcg -> 1 tab/0.15 • 1/1,000 mcg Based on the Information Provided in the Question, Cancel Out "mcg" 1 tab/0.15 • 1/1,000 mcg • 75 mcg -> 1 tab/0.15 • 1/1,000 • 75 Multiply and Divide 75 tab/(0.15 • 1,000) = 75 tab/150 -> 75 tab/150 = 0.5 tab

Oral Medication Dosage Calculation A health care provider orders amoxicillin (Amoxil) 0.25 g p.o. every 8 hours; Available: Amoxicillin 125 mg tablets. How many tablet(s) will the nurse give per dose?

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 tab/125 mg • 1,000 mg/1 g -> 1 tab/125 • 1,000/1 g Based on the Information Provided in the Question, Cancel Out "g" 1 tab/125 • 1,000/1 g • 0.25 g/1 -> 1 tab/125 • 1,000/1 • 0.25/1 Multiply and Divide (1,000 • 0.25 tab)/125 = 250 tab/125 -> 250 tab/125 = 2 tab

Oral Medication Dosage Calculation Each acetaminophen (Tylenol) #3 tablet has 325 mg of acetaminophen and 30 mg codeine. A patient is told to take 2 tablets PO every 4 hours for pain. The maximum safe dose of acetaminophen is 4 g/day. The safe dose of codeine varies with tolerance. Is this dose safe?

Set Up an Equation and, Using Conversions, Cancel Out "mg" 325 mg/1 tab • 1 g/1,000 mg -> 325/1 tab • 1 g/1,000 Based on the Information Provided in the Question, Cancel Out "tab" 325/1 tab • 1 g/1,000 • 2 tab/4 hr -> 325/1 • 1 g/1,000 • 2/4 hr Using Conversions, Cancel Out "hr" 325/1 • 1 g/1,000 • 2/4 hr • 24 hr/1 day -> 325/1 • 1 g/1,000 • 2/4 • 24/1 day Multiply and Divide (325 • 2 • 24 g)/(1,000 • 4 day) = 15,600 g/4,000 day -> 15,600 g/4,000 day = 3.9 g/day Is the Dose Safe? Yes! The dose 3.9 g/day is less than the maximum safe dose (4 g/day.)

Oral Medication Dosage Calculation Your order reads levothyroxine (Synthroid) 100 mcg PO every morning. You have levothyroxine 0.05 mg tablets. How many tablet(s) will you administer?

Set Up an Equation and, Using Conversions, Cancel Out "mg" 1 tab/0.05 mg • 1 mg/1,000 mcg -> 1 tab/0.05 • 1/1,000 mcg Based on the Information Provided in the Question, Cancel Out "mcg" 1 tab/0.05 • 1/1,000 mcg • 100 mcg/1 -> 1 tab/0.05 • 1/1,000 • 100/1 Multiply and Divide 100 tab/(0.05 • 1,000) = 100 tab/50 = 2 tab

Dosage Calculation A client suffering from chest discomfort and shortness of breath is brought to the emergency department due to acute angina pectoris. The healthcare provider orders IV nitroglycerin (Nitroglycerin) 75 mg in 500 mL of 5% Dextrose Water at 100 mcg/min. The nurse will set the pump at which rate (mL/hr)? (Round to the nearest whole number)

Set Up an Equation and, Using Conversions, Cancel Out "mg" 500 mL/75 mg • 1 mg/1,000 mcg -> 500 mL/75 • 1/1,000 mcg Based on the Information Provided in the Question, Cancel Out "mcg" 500 mL/75 • 1/1,000 mcg • 100 mcg/1 min -> 500 mL/75 • 1/1,000 • 100/1 min Using Conversions, Cancel Out "min" 500 mL/75 • 1/1,000 • 100/1 min • 60 min/1 hr -> 500 mL/75 • 1/1,000 • 100/1 • 60/1 hr Multiply and Divide (500 mL • 100 • 60)/(75 • 1,000 hr) = 3,000,000 mL/75,000 hr -> 3,000,000 mL/75,000 hr = 40 mL/hr

Total IV Fluids Received Patient is getting NS at 50 mL/hr in one IV. Patient is getting an IV antibiotic every 8 hours in 100 mL of fluid. Patient is getting a second IV antibiotic every 12 hours in 50 mL of fluid. How much IV fluids will the patient receive in 24 hours?

Set Up an Equation for NS and Cancel Out "hr" 50 mL/1 hr • 24 hr/1 -> 50 mL/1 • 24/1 Multiply (50 mL • 24) = 1,200 mL Set Up an Equation for the First IV Antibiotic and Cancel Out "hr" 100 mL/8 hr • 24 hr/1 -> 100 mL/8 • 24/1 Multiply (100 mL • 24)/8 = 2,400/8 mL Divide 2,400/8 mL = 300 mL Set Up an Equation for the Second IV Antibiotic and Cancel Out "hr" 50 mL/12 hr • 24 hr/1 -> 50 mL/12 • 24/1 Multiply (50 mL • 24)/12 = 1,200/12 mL Divide 1,200/12 mL = 100 mL Add All of the Answers Together to Find How Much IV Fluid the Patient Will Receive in 24 Hours 1,200 mL + 300 mL + 100 mL = 1,600 mL