Pharmacology

Exam 1

list the factors that influence drug absorption

surface area, ph of body fluid where absorbed, drug route, blood flow, food

absorption

process of moving a drug from the site of administration to the blood stream

Why is it important for a nurse to have an understanding of a prototype drug

prototype drug helps predict actions and adverse side effects of other drugs in the same class.

prototype drug

oldest and best understood drug from the class to which all other medications in a class are compared to

prototype information to know

classification (pharmacologic and therapeutic)

mechanism of action

therapeutic effect and indications

adverse effects

contraindications

precautions and nursing responsibilities

Why do you need to know about all the medications a patient is taking including over-the-counter (OTC), vitamins, and herbs

these may interact with prescription meds

List 3 types of information that the nurse should obtain prior to ADMINISTERING A DRUG

medical history

physical assessment

adverse effects

also important o know why this drug for this patient, how the pt is now and what bad things can happen to look out for

5 parts of nursing process

Assessment

diagnosis

plan

intervention/implementation

evaluate

Explain how pharmacokinetics of a drug are altered

small bowel resection would be slower due to less surface area

renal insufficiency would be (kidneys) less excretion

pulmonary disease , smoking increases cyp enzyme so may be faster or slower metabolism depending on drug

liver impairment will slow metabolism

simple diffusion

movement from high concentration to low concentration

drugs that are small, nonionized and lipid soluble will use simple diffusion

large molecules need energy to cross

What type of patients are at risk for drug interactions? Think about age and alcohol use weekly, those with multiple chronic diseases, swallowing issues and which would or would not be a risk for drug interaction.

infants due to underdeveloped liver

adults have decreased metabolic activity

liver disease, kidney disease, having two or more conditions, diabetes, heart disease.

chronic alcohol users and tobacco use induce CYP enzyme

Compare routes of drug administration and absorption time/speed of those routes. What happens to the absorption of the local anesthetic administered subcutaneously if a vasoconstrictor is added to that local anesthetic?

enteral drugs: PO, Ng, GT, buccal, sublingual, PEG: second fastest

parenteral drugs: IV, IM ,Subq: fastest

topical: slowest

vasoconstriction slows absorption and local anesthetic will stay in tissue longer

Be able to explain how disease in (which organ) ___ can impact the risk for toxicity for a drug with a long half-life

Liver

unable to metabolize so drugs stay in blood longer and becomes toxic level

half life of drug

time required for the plasma concentration or total amount in the body to decrease by 50%

4 half lives to eliminate drug

Be able to explain what happens when a patient is taking a drug that is metabolized by a CYP enzyme and is also given a second drug that is an inducer of the same CYP enzyme

metabolism will be increased of the first drug and may use it all up causing that dose to not reach therapeutic effects

agonist drug

activates receptor and increases action

antagonist drug

stops action you do not want by binding to receptor and keeps actual chemical from binding, so no action

is narcan an antagonist or agonist

naloxone is an antagonist that will reverse effects of opiate overdose

What should you do (as the nurse) if you notice a provider writes several prescriptions for a patient and they are from the same class as drugs the patient is already on at home?

notify provider there are two drugs from the same class and ask why

make sure they are in therapeutic range and not toxicity range

What would your response be if you, as the nurse, are administering a blood pressure medication to your patient and they say “That does not look like the pill I take at home

validate their concern, check and comfirm

explain multiple trade names or brands that look different but are same generic drug

Practice how to figure how much drug is left if the half-life is 2 hrs. 4hrs, 8 hrs. The drug is 100mg dose given at 0700 (7am), at what time will there be only 25mg remaining?

2hr half life 1100 25mg

4hr half life 1500 25 mg

8hr half life 2300 25 mg

adverse effects

are undesirable, unexpected, and possibly harmful after administration

allergic reaction

hyper response of immune system, nothing to do with pharmacological actions of drug

anaphylaxis

severe life threatening immune response

increase excretion of a basic drug

give acid to increase excretion; make urine acidic to excrete alkaline/basic drugi

increase excretion of acidic drug

give basic to increase excretion; make urine alkaline to excrete the acid

what do to if medication error is made

let the patient know, assess pt frequently, notify provider, document incident report

5 rights for med administration

right patient

right drug

right dose

right route

right time

Why do you think that a husband and wife taking the same medication for hypertension (HTN=high blood pressure) would be taking different doses

everyone responds differently, based off of weight, metabolism, comorbidities

Therapeutic classification

What is being treated by the drug, what condition is being treated

Usually starts with anti

Pharmacologic classification

How the drug acts, mechanism of action, or how the drug produces the affect in the body

4 parts of pharmacokinetics

Absorption distribution metabolism excretion

First pass effect

Drubs absorbed from the stomach and small inserting first pass through the liver where they may be inactivated

Enteric coated tablets

Designed to desolve in alkaline envir

Ionization of drug

Ionized: not passed through the plasma membrane

Nonionized: passed through the plasma membrane