Pharmacology part 1: Final Flashcards
What are chemical names
state the chemical structure or chemical classification
what are generic names
shortened version of chemical
what are trade names
brand names
i.e. tyelenol
pts form recognition of the name
What are generic equivalents
drugs that are marketed by generic names after the patent has expired
less expensive than trade names
what are the stages of FDA testing/approval
1 - preclinical (animal trials); 1-2 years
2 - clinical trials; 3 phases; ~5-6 years total
3- approved for market; market studies/feedback
what are the 3 phases of the clinical trial for the FDA testing
phase 1 = healthy volunteers to test side effects
phase 2 = small pt sample (200-300) to test effectiveness of drug for treatment
phase 3 = larger sample; few thousand; determine of drug is safe for larger population
what are pharmocokinetics
what the body does to the drug
how is it absorbed, metabolized, excreted, etc
what are pharmacodynamics
what the drug does to the body
i.e. how it lowers pain, BP, motor fxn, etc
what is expedited review
if a drug has exceptional need or beneficial effects
saves time
drug is used in general population before clinical trials and testing continues after drug is already in use
what are orphan drugs
drugs indicated for a very small population
FDA subsidizes companies to fund production of drugs
what is off label prescribing
hasnt been approved by FDA for condition other than it’s original purpose
BUT if a doctor sees a benefit that is not the original purpose of the drug they can still prescribe that medicine because the FDA is not allowed to tell doctor’s how to practice medicine
what are the implications of drug testing/approval
-cost of the drug
-whether it is available in the US and/or other countries
-failure to identify serious side effects
describe the dose response concept
if the dose is too low = no response
threshold dose = when you first start seeing results from drug
too high and you reach the ceiling effect (no more added benefit of more drugs)
curve contains a therapeutic range where benefits are most advantageous to pt
what is drug potency
related to dose that causes specific response in a specific magnitude
i.e. comparing 2 drugs; the one that causes a response at a lower dose is the more potent drug compared to the one that requires a higher dose for the same response
how do you find the therapeutic index and what is the significance
TI = TD50 (median toxic dose) / ED50 (median effective dose)
higher the TI the safer the drug
there is no cut off point
what is the quantified cumulative D-R curve
specific response in a group
used to determine drug safety
median effective dose = dose that caused benefits in 1/2 sample
median toxicity dose = dose that causes toxic effect in 1/2 sample
what is absorption
route of administration
more direct = more effective
what is enteral absorption
through alimentary canal
oral
lingual/sublingual
buccal
rectal
easy but less predictable
what is parentral absorption
i.e. injection, inhalation, topical, or transdermal
more difficcult to administer but more predictable
what is bioavailability
% dose in the bloodstream
only with oral or transdermal since all IV drugs are already 100% into bloodstream (doesnt apply)
what is the first pass effect
oral medicine is absorbed in the GI tract and then destroyed in the liver
first pass of breaking down drug in body
important to determine what % of the drug will survive this first pass for dosage purposes
what is distribution
drugs typically cross membrane and tissue to reach target
what affects distribution
administration route
properties of drug
binding to plasma proteins
various barriers or carriers in body
what is volume of distribution
amount of drug administered / concentration in plasma
about = 42 means even distribution in body
more than 42 means drug is retained in tissues
less than 42 means drug is retained in plasma
primary storage sites for drugs in body
fat, muscle, bone, liver, and kidneys
concerns with drug storage
redistribution or local tissue damage
how are drugs metabolized
active form of drug is changed chemically to inactive or less active byproduct
becomes more polar/water soluble and easier for kidneys to excrete
liver = primary site
aka biotransformation
how do enzymes metabolize drugs
phase 1 rxns like oxidation, reduction, or hydrolysis
phase 2 rxns: conjugation (add 2nd molecule to phase 1by-product
sites of excretion
primary = kidneys
other = lungs, GI, sweat, or breast milk
what is clearance
rate a drug can be completely removed from body
variables that affect clearance
blood flow to an organ or how well that organ works
what can impair clearance of a drug
illness
poor blood flow
lower clearance = prolonged side effects or effects of drugs
what is half life
time for half the drug to leave the body
most common way to assess how long drug effects will last
explain how drug administration/dosing schedule can effect levels of drug in body
drugs administered with IV can maintain a stable level in blood stream
drugs given intermittently have peaks/troughs in plasma
factors that can affect normal pharmokinetics
disease
age
genetics
gender
body comp
diet
other chemicals
physical factors like heat/cold
implications of pharmacokinetics for rehab
timing of therapy sessions around peaks/troughs (oral peak = 30-60 min after taking)
effects of absorption/distribution via heat, exercise, cold, etc
recognize improper drug response
