Part 1 Pharmacology Flashcards
what is pharmacology broken down into?
pharmacotherapeutics & toxicology
what is pharmacokinetics?
what body does to drug
what is pharmacodynamics?
what does drug do to body
what are the three names drugs are identified as?
generic
chemical
trademark
a drugs ____ name is usually shortened to a form the drugs _____ name?
chemical to form generic
what is a generic equivalent?
drug marketed by generic name after the patent has expired
generic forms typical less expensive than brand name products
how is a generic equivalent “bioequivalent” to a brand name?
- same type & amount of active ingredient
- uses same administration route
- same pharmacokinetic profile
- found to have same therapeutic effects
what is the role of the FDA in drug approval?
-government agency oversees drug testing/approval
-responsible for drug classification
what is the phases of drug testing?
Preclincals
Clinical trials
Phase 1 (healthy volunteers)
Phase 2 (small patient sample)
Phase 3 (larger sample)
Approved for marketing
Phase 4 (post marketing surveillance)
how can a drug get an expedited review?
if the drug has exceptional need or beneficial effects, requested by drug company
what is an orphan drug?
certain drugs are only indicated for small populations
FDA arranges funding from additional sources to subsidize drug development
what are some implications of drug testing/approval?
drug costs
availability in USA vs other countries
failures to identify serious side effects
what is off-labeling prescribing?
prescription of a drug for a purpose that has not been approved by FDA
what is the dose-response relationship?
if dose is too low no response
-response will start to appear at some “threshold dose”
-in theory the response increases as the dose increases
what happens to the response once the dose hits a certain point?
response can plateau which is called maximal efficacy or ceiling effect
what is potency?
related to the dose that causes a specific response in a specific magnitude
-a drug that causes the response at a lower dose is more potent
What does a higher therapeutic index (TI) indicate?
the safer the drug
is there an acceptable TI?
no fixed guidelines
what are the key issues in pharmacokinetics?
-ADME
absorption
distribution
metabolism
excretion
describe absorption?
drugs move from site of administration into another tissue
directly related to route of administration
what are some examples of enteral routes of administration
oral
lingual, sublingual
buccal
rectal
what are some examples of parenteral routes of administration?
injection
inhalation
topical
transdermal
what are the trade-off of the administration; enteral vs parenteral?
enteral: fairly simple, easy but less predictable
parenteral: more difficult, inconvenient but more predictable
what is bioavailability?
percent of the administered dose that appears in the bloodstream
dealing with absorption what is the “first pass effect”?
when drug is administrated orally is then absorbed into the GI tract and enters the liver via hepatic portal vein when this happens some is often destroyed during the first pass through the liver
describe distribution of drugs?
-drugs cross membranes & tissues to reach target site
what can affect the distribution of drugs?
-administration route
-physiochemical properties of drug
-binding to plasma proteins
-various “barriers” & “carriers”
how does drug “storage” occur?
distribution to certain sites result in drug accumulation
primarily storage is in :fat, muscle, bone, liver, kidneys, other organs/tissues
what are the primary problems of storage?
local tissue damage
redistribution
what does metabolism have to do with drugs?
-active form of drug is changed chemically to an inactive or less active byproduct
-often creates more polar, water soluble metabolite that can excreted by kidneys
what is the primary, significant and minor excretion sites?
Primary: kidneys
Significant: lungs, GI tracts
Minor: sweat, saliva, breast milk
what is clearance?
the rate that the drug can be removed completely from the body
what are the two things clearance depends on?
blood flow to the organ
extortion ratio
what is a half-life?
amount of time is takes for 50% of the active form of drug to be eliminated
what happens when a drug is given continuously?
maintain a fairly stable level of drug in the bloodstream
what happens when drugs are given intermittently?
will cause peaks and troughs in plasma levels
what are some factors that affect normal pharmacokinetics?
-disease
-age
-genetics
-gender
-body composition
-diet
-other chemical
-physical factors
what is the implications of pharmacokinetics for rehab?
timing of rehab session with drug peals & troughs
effects on absorption/distribution
helps recognize improper drug responses
