Med Math Dosage Calculations

A client is receiving formula feedings via a feeding tube. The electronic medication record shows that 200 mL is to be infused every 2 hours (06/08/10/12/1400) around the clock. The nurse gives 50 mL of water after each feeding. How much intake will the nurse record from the 06-1400 shift?

1,250 mL/hr 200 mL + 50mL= 250 mL x 5= 1,250

A nurse is preparing to administer cimetidine 300 mg PO twice daily to a client. The amount available is cimetidine 300 mg/ tablets. How many tablets should the nurse administer per dose?

1 tablet

A nurse is preparing to administer clonazepam 1.5 mg PO in 3 equally divided doses every 8 hr for a client who has seizures. The amount available is clonazepam 0.5 mg tablets. How many tablets should the nurse administer per dose?

1 tablet 1.5 mg/ 3= 0.5

A physician prescribed 10 mg of an antibiotic per kilogram of body weight for a client who weighs 165 lbs. How many kilograms does the client weight? How many grams per kilogram would the nurse give?

0.010 g/kg 165/2.2= 75 kg 10 mg/ kg divided by 1000

The client is to receive Docusate sodium 100 mg PO twice daily. What is this dose of medication in grams?

0.1 grams

A nurse is preparing to administer atenolol 50 mg PO daily to a client. The amount available is atenolol 100 mg/ tablet. How many tablets should the nurse administer per dose?

0.5 tablets 50 mg/ 100 mg= 0.5

A nurse is preparing to administer lorazepam 1 mg PO at bedtime. The amount available is lorazepam 2 mg tablets. How many tablets should the nurse administer per dose?

0.5 tablets 1 mg/ 2 mg= 0.5

The client is prescribed allopurinol 250 mg IV per day. The nurse receives allopurinol with a dosage strength of 500 mg/ vial. How many vials of allopurinol should the nurse administer.

0.5 vials 250 mg/ x tablets multiplied by 1 tablet/ 500 mg= 250/500= 0.5

The client had 240 mL of milk, 180 mL of apple juice, and 120 mL of water with the 1000 am medications. What is the total intake the nurse should document in liters on the intake and output form?

0.54 L 240 x 180 x 120=540 mL then convert to Liters

What does 1000 mg equal in mL?

1 mL

What does 1000 mcg equal in mg?

1 mg

The client is to receive Levothyroxine sodium 0.175 mg daily. The available medication is 175 mcg tablets. How many tablets should the client receive?

1 mg= 1000 mcg 1 tablet

A nurse is preparing to administer imipramine 200 mg PO daily divided equally every 12 hours. The amount available is imipramine 25 mg tablets. How many tablets should the nurse administer with each dose?

4 tablets 200 mg/ 2= 100 100/ 25 mg= 4

A nurse is preparing to administer olanzapine 20 mg PO daily. Available is olanzapine 10 mg orally- disintegrating tablet. How many tablets should the nurse administer per dose?

2 tablets 20/ 10= 2

A nurse is preparing to administer diphenhydramine 50 mg PO every 6 hr to a client who has acute dystonia. Available is diphenhydramine 25 mg tablets. How many tablets should the nurse administer per dose?

2 tablets 25+25=50

A nurse is preparing to administer levothyroxine 0.275 mg PO daily to a client. The amount available is levothyroxine 137 mcg/ tablet. How many tablets should the nurse administer? Round if necessary.

2 tablets 275 mg/ 137 mcg= 2.007

A nurse is preparing to administer aspirin 650 mg PO every 12 hours. The amount available is aspirin 325 mg tablets. How many tablets should the nurse administer?

2 tablets 325 x 2= 650

The primary healthcare provider has advised a client with diarrhea to drink eight 10-ounce glasses of water daily. How many milliliter will the client drink?

2,400 mL 8 x 10= 80 oz 80 oz x 30 mL

A nurse receives a presto administer 8,000 mcg of melphalan to a client weighing 40 kg. The dosage strength of the medication is 2 mg/ tablet. How many tablets should the nurse administer to the client? Round your answer as a whole number.

4 tablets 8,000 mcg/ 1,000 mcg= 8 mg 8mg/ x tab multiplied by 1 tab/ 2 mg= 8/2= 4

The primary healthcare provider prescribes a cough syrup 0.4 g every 4 hours. The dosage strength of the syrup is 100 mg/ 5 mL. How many teaspoons will the nurse instruct the client to take?

4 tsp 0.4g = 400 mg 400 mg/ x mL multiplied by 5 mL/ 100 mg= 2000/ 100= 20/ 5 mL

A nurse is preparing to administer lamivudine 150 mg PO twice a day. Available is lamivudine 100 mg tablets. How many tablets should the nurse administer per dose?

1.5 tablets 150 mg/ 100 mg= 1.5

A nurse is preparing to administer clozapine 300 mg PO daily to a client who has schizophrenia. The amount available is clozapine 200 mg tablets. How many tablets should the nurse administer?

1.5 tablets 300 mg/ 200 mg= 1.5

A nurse is preparing to administer fluoxetine 40 mg PO daily. The amount available is fluoxetine 20 mg/ 5 mL. How many mL should the nurse administer?

10 mL 5 + 5= 10

The physician ordered 500 mL D5 1/2 NS to run at 100 mL/ hour with a drop factor of 60 gtt/ mL. Calculate the IV flow rate in gtt/ minute. Round off to the nearest whole number.

100 gtt/ min 500/ 100= 5 hours 500 mL/ 300 min multiplied by 60

The client is to receive Kanamycin sulfate 1 g PO every 6 hours for 5 days. What is this dose of medication in milligrams?

1000 mg

A nurse is preparing to administer amantadine 150 mg PO every 12 hr. Available is amantadine 50 mg/ 5 mL syrup. How many mL should the nurse administer per dose?

15 mL 150mg/ 50mg= 3 5mL multiplied by 3= 15

A nurse is preparing to administer indomethacin 75 mg PO 2 a day. Available is indomethacin 25 mg/ 5 mL. How many mL should the nurse administer per dose?

15 mL 75 mg/ 25 mg multiplied by 5= 15

A nurse is preparing to administer phenytoin 75 mg PO every 6 hr. Available is phenytoin 25 mg/ 5 mL. How many mL should the nurse administer?

15 mL 75 mg/ 25 mg= 3 3 x 5 mL= 15 mL

The physician ordered 2500 mL of NS to infuse in 150 mL/ hour with a drop factor of 15 gtt/ mL. How long will this IV run?

16 hours and 36 min 2500 mL/ 150 mL per hour= 16.66

The physician ordered hydrocortisone sodium succinate 250 mg in 1000 mL over 10 hours with a drop factor of 10 gtt/ mL. What is the correct IV flow rate in drops per minute? Use the standard formula to solve this problem. Round off to the nearest whole number.

17 gtt/ min 1000 mL/ 600 min multiplied by 10= 16.66

A nurse is preparing to administer lithium 300 mg PO every 8 hr. Available is lithium carbonate 150 mg capsules. How many capsules should the nurse administer per dose?

2 capsules 150 mg + 150 mg= 300 mg

A nurse is preparing to administer celecoxib 200 mg PO daily divided into two equal doses. Available is celecoxib 50 mg capsules. How many capsules should the nurse administer with each dose?

2 capsules 200 mg/ 2= 100 100/ 50 mg= 2

An adult client has been prescribed streptomycin intramuscularly (IM) 1g/ day. Each mL of streptomycin contains 500 mg. How many mL will the nurse administer?

2 mL 1 g= 1000 mg 1000 mg/ 500 mg= 2

A nurse is preparing to administer digoxin 0.25 mg PO daily. The amount available is digoxin 0.125 mg tablets. How many tablets should the nurse administer?

2 tablets 0.125 + 0.125= 0.25

A client with severe pain has been prescribed 10 mg of oxycodone. The bottle of medication is labelled with dosage strength of 5 mg per tablet. How many tablets should the nurse administer to the client? Round your answer as a whole number.

2 tablets 10 mg/ x tablets multiplied by 1 tablet/ 5 mg 10/5= 2

The physician ordered a unit of 250 mL packed red blood cells to infuse over 4 hours with a drop factor of 10 gtt/ mL. Calculate the correct IV flow rate in mL per hour. Round off to the nearest whole number.

63 mL/ hr 250 mL/ 4 hr

A client had the following clear liquid dinner: 4 tbsp of apple juice, 8 oz of beef broth, 4 oz of orange gelatin, and 1/2 pint (500mL = 1 pint) of tea. What is the total intake the nurse should document in milliliters on the intake and output form?

670 mL 4 tbsp= 60 mL 8 oz= 240 mL 4 oz= 120 mL 1/2 pint= 250 mL

The physician ordered 1000 mL of D5W to infuse at 125 mL/ hour with a drop factor of 10 gtt/ mL. How many hours will this IV run.

8 hours 1000 mL/ 125 mL

The physician ordered 500 mL NS to run over 6 hours with a drop factor of 20 gtt/ mL. Calculate the correct IV flow rate to set on the infusion pump.

83 mL/ hr 500mL/ 6 hr= 83.333

What does 1 kg equal in lbs?

2.2 lbs

The physician ordered a total of 1500 mL of NS to infuse at 75 mL/ hour with a drop factor of 15 gtt/ mL. How many hours will this IV run?

20 hours 1500 mL/ 75 Ml per hour

The physician ordered 1000 mL of D5W to infuse over 16 hours with a drop factor of 20 gtt/ mL. Calculate the correct IV flow rate in drops per min. Round off to the nearest whole number.

21 gtt/ min 1000 mL/ 960 min multiplied by 20= 20.833

The physician ordered 500 mL of D5W to infuse over 8 hours with a drop factor of 20 gtt/ mL. Calculate the correct IV flow rate in drops per minute. Round off to the nearest whole number.

21 gtt/ min 500 mL/ 480 min multiplied by 20= 20.833

What does 1 cup (8oz) equal in mL?

240 mL

The physician ordered 1000 mL NS to infuse over 10 hours with a drop factor of 15 gtt/ mL. Calculate the correct IV flow rate in drops per minute. Round off to the nearest whole number.

25 gtt/ min 1000 mL/ 600 min multiplied by 15 gtt/ mL

What does 1 tbsp equal in tsp?

3 tsp

How many milliliters would the nurse document on the intake and output form as being absorbed from a 1 L bag if 125 mL was left in the bag?

875 mL 1000 mL= 1 L - 125 mL

A client weight 4.5 kg. How many pounds should the nurse document on the chart? Round to the nearest tenth.

9.9 lb 2.2lb x 4.5 kg

The physician ordered clindamycin 900 mg in 75 mL over 30 minutes with a drop factor of 15 gtt/ mL. What is the correct IV flow rate in drops per minute? Use both the standard formula and dimensional analysis to solve this problem. Round to the nearest whole number.

38 gtt/ min 75 mL/ 30 min multiplied by 15= 37.5

What does 1 oz equal in mL?

30 mL

A client with rheumatoid arthritis has been prescribed indomethacin 0.15 g per day. The nurse has indomethacin oral suspension available at 25 mg/ 5 mL. How many milliliters of indomethacin should the nurse administer to the client? Round your answer as a whole number.

30 mL 0.15g= 150 mg 150 mg x 5 mL = 750 mL 750 mg/ 25 mg= 30 mL

A patient with a bacterial infection has been prescribed 0.18 g of doxycycline. The dosage strength of the available medication is 6 mg/mL. Calculate the amount of doxycycline oral suspension to be administered per dose to the client in mL. Round your answer as a whole number.

30 mL/ dose 1,000 mg= 1g 180 mg/ x tab multiplied by 1 tab/ 6 mg= 180/6= 30

A client on a fluid-restriction diet is directed to take his daily medication with 120 mL of water. The client will use a measuring cup and pour how many ounces?

4 oz 1 oz= 30 mL 120 mL/ 30 mL

A client has an order for 1200 mL of water by mouth every 24 hours. How many ounces does the client have to drink?

40 oz 30 mL= 1 oz 1200mL/ 30mL

A primary healthcare provider orders tobramycin intramuscularly (IM) 6.6 mg/ kg daily. The dosage strength of tobramycin is 10 mg/ mL. How many mL will the nurse administer for each dose to a 158 lb client?

47.4 mL 2.2 lbs= 1 kg 158/ 2.2= 71.82 kg 71.82 kg x 6.6= 474 474/ 10= 47.4

What does 1 tsp equal in mL?

5 mL

The physician ordered 1000 mL of NS to run at 167 mL/ hour. How many hours should it take for the IV to infuse? Round off the nearest whole number.

6 hrs 1000 mL/ 167 mL= 5.988