Pharmacologic Principles Flashcards
Topical route
skin, eyes, ears, nose, lungs, rectum, vagina
how fast do topical powders/solutions work?
immediately
do ointments/gels/creams have a local or systemic effect?
local, but some can be systemic (nitro)
Transdermal patches deliver a…
constant amount of medication
how fast is absorption from inhaled meds?
fairly rapid
what are suppositories?
a med put into the rectum or vagina
where is the enteral route absorbed
mucosa of the stomach, small, or large intestine
enteral is any form of medication the enters through…
the mouth
immediate release pills release…
all active ingredients quickly
extended release pills…
release slowly
syrups
contain active ingredients and large amounts of sugars
suspension/emulsion
powder mixed with liquid activates the medicine when shaken
elixir
sweetened alcohol and water
lozenges
never chewed or swallowed, placed in mouth & dissolves over time
Sublingual
placed under the tongue
parenteral
the fastest, any route other than GI tract (most common is IV)
first-pass effect
breakdown of potency of a medication in liver, reduces bioavailability of drug to <100%
parenteral bypasses the…
first-pass effect on liver
topical also bypasses…
the first-pass effect
what factors affect absorption?
- ability for drug to dissolve/solubility
- blood flow to administration site
- body surface area
During biotransformation (metabolism), the drug is altered to a…
less active form
half-life
- time required for 50% of a drug to be removed from the body
- after 5 half-lives, most drugs are considered eliminated
steady state
amount of drug eliminated is equal to the amount of drug absorbed
(rate in = rate out)
onset
how quickly a medication will work
peak
when the medication will reach maximum effectiveness (highest level in blood)
trough
lowest level in blood
duration
how long the pain relief will last
absorption
movement of drug into the bloodstream
mechanism of action
effects vary based on cell structure of the intended target
drug-receptor interaction
drug receptor interaction is the joining of the drug molecule w/ a reactive site on the surface of a cell or tissue
agonist
drug binds to receptor (ex. morphine will trigger all opioid receptors in the brain)
antagonist
drug binds to receptor & has no response (ex. Narcan will block all opioids from attacking)
acute therapy
needed to sustain life
ex. vasopressors, chemo
maintenance therapy
prevents progression of a disease or condition
ex. BP meds, birth control
supplemental therapy
provides body what it needs to function normally
ex. insulin
palliative therapy
providing relief from symptoms, improving quality of life
ex. Tylenol for fever
supportive therapy
maintains integrity of body function while recovering from surgery/trauma
ex. IVF or blood products
prophylactic therapy
preventing an illness
ex. vaccines
empiric therapy
symptoms of infection but do not have labs to confirm yet
ex. broad spectrum antibiotics
tolerance
decreased response to repeated drug doses
dependence
need for the drug
psychological dependence
need for euphoric effect of the drug
physiologic dependence
physical dependence; withdrawal symptoms
foods/drinks that may interact with drugs
leafy greens, dairy, alcohol, grapefruit juice, wine, aged cheese
additive effect
two drugs w/ similar action are given together. additive effect so smaller doses of each drug can be given (1+1=2)
ex. codeine & Tylenol
synergistic effect
combined effects are greater than sum effect of each drug alone (1+1=>2)
ex. aspirin & warfarin = bleeding
antagonistic effect
two drugs working together that will produce different effects. combined effect is less than sum effect of each drug given alone (1+1=<2)
ex. insulin & glucacon
incompatibility
chemical deterioration of one or both drugs
idiosyncratic reaction
unexpected reaction
drug-drug interaction
when the presence of two or more drugs in the body produce unwanted effects (enhances or decreases)
older adult lifespan considerations
- decline in organ function
- more likely to result in adverse effects & toxicity
- polypharmacy
- not enough pills due to finances
polypharmacy
taking five or more meds each day
drug polymorphism
slow or rapid acetylators, effects on a patient’s age, gender, body comp on pharmocokinetics
disadvantages to OTC meds
- delay in treatment
- treating symptoms; not the cause
- cost
- patient education
pharmacotherapeutics
intended use & effect of the drug
pharmacodynamics
mechanisms of the drug
areas with the biggest blood supply
heart, liver, kidneys, brain
areas with slower distribution
muscle & fat
pharmacokinetics
what happens to the drug when it enters, travels through, & leaves the body
routes of parenteral administration
intravenous, intradermal, intramuscular, subcutaneous
