Pharmacology Test #1 (ADN-111)
Pharmacodynamics Therapeutic Index-
*therapeutic effect- I & R (International ratio) needs to maintain between 2-3, tells how well the blood is clotting > 6 = blood is too thin * DIG level - 0.4-0.8 Range of drug in the body, if its too high, you would stop the medication until you can get it back into therapeutic index range.
Examples of drug classifications
- ACE inhibitors (how well does it work) > antihypertensive*Overall- Antihypertensive*Family- Diuretic- Lisinopril > ending in "pril" = belongs to the same family as Benazepril
Right medication
- Date and time the order is written - Drug name - Drug dosage - Route of adm - Frequency and duration of adm - Any special instructions for withholding or adjusting dosage - Providers signature - Signature of person taking the order * Check to make sure its the right drug 3 times * Patient questions drug, check it again, then inform the patient of the new medication
When the nurse administers a 50 mg dose of a drug with a half-life of 6 hours, how many milligrams will remain in the body after 24 hours?
-3.13 mg Just divide 24 by 6 = 4 then dived 50 by 4
Pharmacokinetics Free drugs-
-Able to exit blood vessels and reach their site of action
Pharmacodynamics Agonists-
-Activate receptors -Produce desired response Ex: Levothyroxine (synthroid)= replacement of thyroid hormones
What is a near miss?
-Almost made a medication error -Document it so it doesn't happen again
Drug classifications known to be teratogenic
-Androgenic and estrogenic hormones -ACE inhibitors, ethanol, tetracycline -Thalidomide, vitamin A, Warfarin -Angiotensin II receptor antagonists -Anticonvulsants, antimanic agents, antithyroid -Chemotherapy, statins, cocaine
How does chronic renal failure or liver failure affect medication administration?
-Kidneys and the liver play a key role in the excretion of medications, so if they are no longer working, you will need to give medications that will be excreted by a different organ/route.
All ages
Distribution- Depends on pH, body water concentrations, fat tissue, protein-binding, cardiac output, and blood flow Metabolism- Genetics, smoking, diet, other medications, liver disorders Excretion- Full adult function occurs at 9-12 months
Synergistic Effect
Effects is much greater than effects of either drug alone
Pharmacodynamics Nonspecific-
Ex: Atropine Ex: Loperamide (Immodium) -acts on cholinergic receptors
Single (one time)
Given one time only for a specific reason
prn
Given when the patient requires it
Pharmacodynamics Peak-
Highest concentration in blood -Ex: Insulin Lispro> peak = 1-2 hours (as low as its going to go)
Which patient has the greatest percent of body water?
Infant
Which route of administration has the fastest rate of distribution?
Intravenous
Pharmacokinetics
Is the process of drug movement through our body that is necessary to achieve drug action
Pharmacodynamics Drug levels-
Keep them at a drug level between the therapeutic index * Advance volume- can lead to drug tolerance
Pharmacodynamics Duration-
Length of time taken for a drug to exert a therapeutic effect -Ex: Insulin Lispro > duration = 3-4 hours (works up to 4 hours)
Official Name-
Listed by FDA
What is a physiologic change seen in older adults that has an effect on drug administration?
Lower Cardiac Output
Nurses are legally required to document medications that are administered to patients. The nurse is mandated to document what?
Medication after administering it
Nurses are legally responsible to document medications that are administered to patients. The nurse is mandated to document?
Medication after administering it
Prescriptions
Medication to be taken outside of the hospital
What medications can be crushed?
Medications that are not a extended release/enteric coated tablets
Complete medication order
Must include the clients full name, the data and the time of the order, the name of the medication, the ordered dosage, and the form of the medication, the route of administration, the time or frequency of administration, and the signature of the ordering physician.
Older adults are at risk for taking many medications together, this is known as?
Polypharmacy
Absorption
Process by which drugs are absorbed in the body, most common is via GI tract, other routes are parenteral and topical
Right dose
Right does- refers to verification by the nurse that the dose adm is the amount ordered and that it is safe for the pt - Nursing interventions for right dose: calculate the drug dose correctly. Check the American Hospital Formulary
Which drug schedule indicates drugs with the highest risk for abuse?
Schedule 1
Premature
Slower gastric emptying time, may allow increased absorption
Additive Effect
Sum of effects of two drugs
Displacement Effect
The displacement of the first drug from protein-binding site
Interference Effect
The first drug inhibits the metabolism or excretion of the second drug, thereby causing increase activity of the second drug
Incompatibility Effect
The first drug is chemically incompatible with the second drug
Pharmodynamics
The study of the effects of drugs on the body, and how it influences cellular physiology.
Pharmacodynamics Onset-
Time it takes for drug to reach minimum effective concentration -Ex: Insulin Lispro > onset = 5 mins
Enteral administration
Via the gastrointestinal tract by the oral, rectal, or nasogastric routes
Now
When a medication is needed right away, but not STAT
Antagonistic Effect
one drug reduces or blocks the effect of the other
Buccal administration
placing drug between tongue and cheek
Medication Legislation and standards
∆ Federal regulations - Pure Food and Drug Act - Food and Drug Administration (FDA) - MedWatch program ∆ State and local regulation of medication ∆ Health care institutions and medication laws ∆ Medication regulations and nursing practice (Nurse Practice Acts)
Liquid medications
measure out at eye level looking at the meniscus line
Legislation Regarding Drug Use
- Federal Food, Drug and Cosmetic Act (1938, 1952, 1962) - Controlled Substances Act (1970)
Laws for nurses
- Maintain skills for competency - monitor for adverse effects - safe guard medications
Controlled substance
- Manufactures prescribers, and dispensers must register with the DEA * Requirements must be met to dispense scheduled medications - Controlled substances in hospitals * Inventory and dispersion controlled records
JCAHO (Joint Commission on Accreditation of Healthcare Organizations) "Do Not Use" List: Abbreviations, Acronyms and Symbols
- Not use: U, u (unit), Potential Problems: mistaken for "0" (zero), the number "4" (four) or "cc", Use instead: write "unit" - Not use: IU (International Unit), Potential Problems: mistaken for IV (intravenous) or the number 10 (ten), Use instead: write "International Unit" -Not use: Q,D, q,d, qd, (daily), Potential problems: mistaken for each other, Use Instead: write "daily" - Not use: Q,O,D, QD, qod, oqd (every other day), Potential problems: period after the Q mistakes for "I" and "O" mistakes for "I", Use instead: write "every other day" - Not use: trailing zero (X0 mg), Potential problem: decimal point is missed, Use instead: write X mg - Not use: lack of leading zero ( X mg), Potential problem: decimal point is missed, Use instead: write 0.X mg
Pharmacodynamics: Drug response relationship
- Potency - Therapeutic Index - Drug levels
Further Classification
- Prescription require an order by a health professional licensed to prescribe drugs - Nonprescription: over-the-counter (OTC) drugs sold without a prescription - Illegal or recreational drugs: used for non-therapeutic purposes; obtained illegally
Right documentation
- Requires the nurses to immediate record the appropriate information about the drug adm. 1.) the name 2.) dose 3.) route 4.) time and date 5.) nurse initials or signature. Document the pt response to 1.) opioids 2.) non-opioid analgesics 3.) sedative 4.) antisemitic's (nausea medication)
Right route
- Right route is necessary for adequate or appropriate absorption. The route is ordered by the provider and indicate the mechanism by which the med enters the body. - Nursing interventions: assess the pt ability to swallow before adm. Do not crush or mix medications. Use aseptic techniques what adm drugs, adm drugs at appropriate sites for route. Stay with the pt until oral drugs have been swallowed.
Right time
- Right time- is the time the prescribed dose is ordered to be administrated. Daily drug dosage are given at specific times during the day, such as twice daily (BID). Nursing interventions: adm drugs at the specified times. Adm drugs that are affected by food 1 hour before 2 hours after meals. Adm drugs that can irritate stomach with foods. Adjust the medication schedule to fit in the pt lifestyle.
Right Patient
- Verify client by checking the identification bracelet. Some facilities put the clients photo on his or her health record - Distinguish between 2 clients with the same last name, warning highlighted in a bright color on ID tools, such as med cards, bracelet, or Kardex .- Some institutions have ID bracelets coded for allergy status. Be aware of policy's
Drug Classification
-Body system classification (cardiovascular, gastrointestinal, etc.) - Therapeutic use or clinical indications (antihypertensive, anti-ulcer, ect.) - Physiologic or chemical action (ACE-inhibitor, H2 receptor antagonists, ect.) - Sanders has it as pharmacotherapeutic and clinical (Lisinopril pharmacotherapeutic- ACE 1 and clinical - Antihypertensive) - Classification is based on mechanism of action and includes only those drugs that have the same or similar mechanism of action.
Pharmacokinetics Absorption-
-Drug is transferred from entry site into body's circulatory fluids -Absorption rate depends on route, blood flow, and solubility of the drug *Subcutaneous and intramuscular injection absorption is affected by circulation -Intravenous medications are absorbed faster -Topical medications applied to the skin can be influenced by skin thickness and hydration
Pharmacodynamics - Therapeutic drug monitoring
-Drug peak level -Trough drug level
Pharmacokinetics Distribution-
-Drugs are transported throughout the body by fluids to the sites of action * protein binding and fat solubility affect distribution -Organs with largest blood supply receive the distributed drug most rapidly -Some drugs cannot pass through the blood-brain barrier or the placental barrier
Oral administration
-Easiest and most desirable route. -Food sometimes affects absorption. -Aspiration precautions. -Enteral or small-bore feedings: *Verify that the tube location is compatible with medication absorption. *Use liquids when possible. *If medication is to be given on an empty stomach, allow at least 30 minutes before or after feeding. *Risk of drug-drug interactions is higher
Pharmacokinetics Excretion-
-Elimination of drug metabolites and some of the active drug from the body -Kidneys are the major organ of excretion, some excreted in feces -Drug excretion (elimination) *Kidneys (major excretion organ) -Creatine clearance -BUN (blood urea nitrogen) -Glomerular filtration rate: goes down close to the teens in number, if they go up it means your retaining *Liver (bile) *Feces *Lungs *Saliva, sweat, breast milk
Pharmacokinetics Half-Life of Drugs-
-Factors modifying the quantity of drug reaching a site of action after a single oral dose *how often you will get the drug
Verelan? VERAPAMIL HCL?
-Generic/chemical name -Brand name
Pharmacokinetics Loading dose-
-Give a higher dose, then a lower dose 24 hours later
Pharmacokinetics Protein binding-
-Has to have a lipid protein to transport it Ex: Warafin (blood thinner) if the drug is less than 10% protein binding > known as weak drugs
Controlled Substances Schedules:
-I : heroin (worst one) -II : hydrocodone - III : codeine - IV : Alprazolam (Xanax) - V : containing no more than 200 mg of (Codeine/guaifenesin)
Generic / Chemical name
-Important to know because formularies use them -NOT capitalized - Nonproprietary or generic name used to describe an official drug in Canada
When a medication error occurs:
-Patient safety and well-being are the top priorities -First, assess and examine the patient's condition -Second, notify the health care provider -Third, Report the incident to the appropriate person in the agency -Forth, fill out an incident report *Patient's identification *Location and time of incident- accurate, factual description *Action *signature
Pharmacodynamics Potency-
-Potency: amount of drug needed to elicit a specific physiological response to the drug * higher level potency= lower amount of drug needed
Pharmacodynamics Antagonists-
-Prevent receptor activation -Block response Ex: Metaprolol (Ioprol)= blocks beta response of the sympathetic nervous system
5+5, or 6
-Right documentation *Baseline data *Vs/labs -Right Education *Information about the medication *Names *Results *Side effects, diet -Right Evaluation *Did the medication do what is was suppose to do -Right to refuse
Topical medication administration
-Skin applications -absorbed through the skin at a more routine route *any time you change a patch (always wear gloves!!)
Biotransformation
-The process whereby the body inactivates drugs -Primary organ of metabolism is the liver, other sites are GI tract and lungs
Pharmacokinetics Metabolism-
-The process whereby the body inactivates drugs: Biotransformation -Primary organ of metabolism is the liver, other sites are GI tract and lungs
What does enteric coated mean?
-Timed-release -Cannot be crushed
Pharmacokinetics Drug movement from GI tract to liver-
-Via portal vein -First pass effect -Bioavailability *Refers to the active drug available *Ivy-directly into the circulatory system= absorbed
percutaneous administration
-absorbed through the skin and mucous membranes -inhalation, sublingual, or topical
Pharmacokinetics Factors affecting absorption-
-blood circulation -pain, stress > vasoconstriction= increase in BP -Food texture, fat content, temperature -pH -Route of admission * Stress slows down the digestive system = which can reduce the amount of medication absorbed
Pharmacodynamics Nonselective-
-drugs that effect non-specific receptor sites Ex: Epinephrine- used for allergic reactions (its a adrenergic beta blocker) **** Beta 1- only 1 heart **** Beta 2- you have 2 lungs Ex: Metoperal- most selective (Beta 1= affects the heart)
Pharmacodynamics Drug peak level-
-increase in plasma concentration of a drug at that time> shows a rate of absorption = blood samples should be drawn at the time of peak level > time/route of absorption of medication
Brand or Trademark
-registered by manufacturer - CAPITALIZED
Critical thinking- six rights
1.) Right medication 2.) Right dose 3.) Right patient 4.) Right route 5.) Right time 6.) Right documentation
Pharmacokinetics Liberation-
A drug is released from the dosage form
Neonates
Absorption- IM (inter-muscular absorption) erratic, reduced gastric acidity Distribution- Reduced protein-binding Excretion- 35% of the renal capacity of an adult
Infants
Absorption- Topical absorption increased Distribution- Higher total body water content, requiring higher dose on mg/kg basis, lower body fat Metabolism- Enzymes take several weeks to a year to develop Excretion- have 15% of the renal capacity of an adult
Geriatric patients
Absorption-IM absorption erratic -Reduced salivary flow makes swallowing difficult -Transdermal absorption hard to predict -Timed-release/enteric-coated tablets cannot be crushed -More alkaline: affects absorption -Slower gastric emptying time -Decreased GI motility and blood flow Distribution- Total body water content decreases Excretion- Decreased renal blood flow, Loss of glomeruli, decreased tubular function
Drug to drug Interactions
Additive effect, Synergistic effect, Antagonistic effect, displacement, interference, incompatibility
Standing or routine
Administered until the dosage has changed, or another medication is prescribed
Pharmacodynamics: Study of the way drugs affect the body- * Primary effect:
Desirable response- the drug is doing what you want it to do
When assessing older adults' renal function, what laboratory value will the nurse monitor?
Blood Urea Nitrogen & Creatine
Which name(s) of a drug should a nurse use when teaching a patient with a new prescription?
Both generic and trade
parenteral administration
Bypasses the GI tract, by using subcutaneous, intramuscular, and intravenous injection
Pharmacodynamics Trough drug level-
Decrease of plasma concentration > shows when the medication is at its lowest level
Pharmacodynamics: Study of the way drugs affect the body- *Secondary effect:
Desirable or undesirable= side effects - side effects can be mild or have adverse effects= more serious side effects *patient needs to be educated about possible drug side effects *Example: Benedryle > secondary effect would be the drowsiness effect of the medication.
Pharmacokinetics ADME
absorption, distribution, metabolism, excretion
sublingual administration
administration of a substance by placing it beneath the tongue
What is first pass?
drugs taken by mouth =low absorption rate because of liver metabolism *Iv's, subQ, do not go through first pass effect*
STAT
given immediately in an emergency
