Pharmacology Exam 1

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pharmacology

study of drugs and how they interact with living organisms

pharmacotherapeutics

the use of drugs to diagnose, prevent, or treat disease or prevent pregnancy

nursing role in pharmacology

education - when and how to take drugs

management

monitoring - monitoring vitals and lab work

drug

chemical agent that produces biological responses in the body, these responses can be desirable (therapeutic) or undesirable (adverse) - every substance can have a good or bad effect or both at the same time

medication

a drug after it is administered

biologic

agents naturally produced in animal cells, microorganisms, or by the body (ex. hormones, vaccines, insulin)

biosimilar

chemically synthesized'; closely related to biological medications

complementary and alternative therapies (cam)

can include substances from plants, foods

non-pharmacologic: massage, music therapy, acupuncture - complementary (in addition to standard of care) or alternative (replaces standard of care)

therapeutic classification

organization based on therapeutic usefulness - what we want this drug to do, the outcome (ex. antihypertensive)

pharmacologic classification

organization based on the way the drug works at the molecular, tissue, or body system level; often represents mechanism of action - how it is done, mechanism on how the drug works (ex. calcium channel blocker)

pharmaceutics

the science of preparing and dispensing drugs, including dosage form design - form and route of drug changes how it works in the body (it is the nurses’ responsibility to give med in the correct route, just cause it is order doesn’t mean we give it)

pharmacokinetics

the study of what the body does to the drug - 4 processes (ADME) - absorption, distribution, metabolism, excretion

how the body deals with medication

understand and predict actions and side effects of medications

absorption

how a medication gets from the site of administration to the bloodstream, primary factor determining length of time for drug to produce an effect, how quickly does this drug circulate throughout the body

bioavailability

extent of drug absorption, affected by route - how much of this drug exerts an effect on the body

first pass effect

large production of a drug is chemically changed into inactive metabolites by the live, smaller amount will be bioavailable, most common routes effected - oral, rectal

factors affecting drug absorption

route, pH of local environment - especially in the stomach, drug, supplement or food interactions - can reduce absorption, drug dose, digestive motility - too fast = may not absorb enough of the drug, constipation = absorbs well can lead to toxicity potential, diarrhea = doesn’t absorb all the way

distribution

how medication gets from the bloodstream to the site of action

delivery is dependent on blood flow

transport of drugs throughout the body - affected by the amount of blood flow to tissues - highly profuse organs get drugs quickly

albumin carries protein-bound drug molecules, drugs bound to album in are inactive, free drugs are active

low albumin levels can impact distribution and lead to toxicity

metabolism

inactivation of medications by enzymes, occurs primarily in the liver, but other organs involved include GI tract, kidneys, and lungs

also known as biotransformation

liver is the primary site

first-pass effect

oral drugs

drug is absorbed - drug enters hepatic circulation, goes to liver - drug is metabolized to inactive form and leaves liver - drug is distributed to general circulation - many drugs are rendered inactive by first-pass effect

excretion

elimination of medications from the body, this usually takes place in the kidneys (via urine), but other routes include saliva, sweat, tears, and feces

renal failure diminished excretion of drugs; dosages must be reduced

adjustments on doses are needed for infants and elderly due to risk of toxicity

half-life

amount of time for a drug to be reduced by 50% in the body

drugs with a shirt half life are excreted quickly

drugs with a long have life leave the body slowly, can increase toxicity

pharmacodynamics

how drugs affect the body, therapeutic effect, mechanism of action - what a drug is doing to our body

agonist

activates a receptor (turns ON) - ex. hydromorphone activate opioid receptors to cause pain relief

antagonist

blocks a receptor (turns OFF) - ex. naloxone is an opioid antagonist blocking opioid receptors and can reverse effects

partial (agonist-antagonist)

acts as both an agonist and antagonist at different receptors - ex. buprenorphine pain control but no drowsy or euphoric effects

pharmacotherapeutics

the clinical use of drugs to prevent and treat disease - ex. using antibiotics to treat infect (cure), using insulin to manage blood sugar in diabetes (management)

acute therapy

patients with rapid onset of illness

more intensive drug treatment

infection - antibiotics

maintenance therapy

prevent progression of disease

treat chronic illness

ongoing blood pressure medication - keeps it in a normal range continuously

supplemental therapy

also known as “replacement therapy”

provides a substance needed to maintain function or body may not be able to make enough

taking/getting what the patient does not have or doesn’t have enough of

ex. insulin for diabetes

palliative therapy

reduce symptom burden on someone

the goal is to make the patient as comfortable as possible and improve the quality of life

relief from symptoms, pain, and stress caused by an illness

not necessarily synonymous with end-of-life

ex. opioid analgesics to relieve pain from cancer

supportive therapy

maintains the integrity of body functions while a patient is recovering from an illness or trauma

is not a direct treatment or cure of illness

Tylenol and fluids for fever from the flu - these don’t cure the flu but it is supporting the body to try and get it somewhat more normal

prophylactic therapy

prevents illness from a planned event

ex. antibiotic before surgery to help prevent the patient from an infection

empirical therapy

treatment of an illness before the illness is specifically identified

drugs are administered where there is a high probability of occurrence based on initial symptoms

ex. antibiotics given for common infectious organism before blood culture/sensitivity results are completed

adverse drug reaction (adr)

unpredictable or undesirable effects, sometimes called adverse drug event (ade) - this is NOT a side effect a side effect is something that is predictable

ex. allergic reaction

tolerance

decreasing response to repeated drug dose (need higher dose because you get more tolerant to drug)

dependence

physiologic or psychological need for drug

physical dependence

physiologic need for a drug to avoid physical withdrawal symptoms (body responds to not having drug in system)

psychological dependence

also known as addition and is the obsessive desire for the euphoric effects of a drug

drug and food interactions

alteration of one drug by another drug or food

teratogenic

drugs that produce structural changes to a fetus

typically most dangerous during first trimester (when all organs are forming)

ex. isotretinoin (acutane)

carcinogen

drugs (or substances) that are known to cause cancer

ex. tamoxifen (can cause secondary cancers elsewhere, used for breast cancer patients)

the 6 rights

right drug

right dose

right time

right route

right patient

right documentation

types of orders based on frequency/urgency

standing orders

prn orders = as needed

one-time orders

stat orders

enteral drug administration

drugs administered orally or through nasogastric or gastronomy tubes

the drug is absorbed into the systemic circulation through the oral or gastric mucosa or the small intestine

oral most common- considered to be the safest and least invasive

undergoes first-pass effect: less bioavailability

topical drug administration

applied locally to the skin or membranous linings of eye, ear, nose, respiratory tract, urinary tract, vagina, and rectum

can produce a local effect topically (ex. icy hot)

can produce systemic effect (ex. fentanyl patch)

*bypasses first pass effect

parenteral drug administration

delivers drugs via needle into the skin, subcutaneous tissue, muscle, or veins

mush more invasive than enteral or topuc

aseptic technique

must be given in correct location

*bypasses first pass effect