module 1 Flashcards
what is pharmacology?
the study of drugs that involves route of administration, how the drug works, therapeutic effects and adverse effects
what is a drug?
traditional drugs or chemical agent
what is a biologic?
antibodies or hormones
what is a natural health products?
herbals, vitamins and minerals
how long does drug approval take in canada?
15 years
how much does total cost of a new drug cost?
800000000 (eight hundred million)
what happens during the drug discovery/preclinical testing?
-in cultured cells, living tissue or experimental animals
-evaluate biological effects, pharmacokinetics, toxicity
-6.5 years
what happens during clinical trial application?
application submitted through health canada, involves alot of paperwork and h
phase 1 clinical trial
20-100 volunteerrs
one year
phase 2 clinical
300-500 sick
2 years
phase 3
500-5000 pt
4 years
new drug submission
report about how well the drug works and safety
1.5 years
phase 4
continues after drug is monitored
what is an eteral drug
involves GI tract
what does the rough endoplasmic recticulum do?
synthesizes proteins
what does the smooth endoplasmic recticulum do?
metabolism of drugs, carbs and steroids
what does the golgi do?
processing and packaging of lipids and proteins
how do drugs pass through the cell membrane
-directly penetrate
-pass through ion/pores
-specific transport proteins
what drugs enter via ion channels and pores?
-very small (under 200da)
-channels are selective
-sodium, potassium and lithium can pass through here
how do drugs pass through the membrance using drugs transporters?
-carrier proteins that move drugs from side to side
-uptake transporters move drug into cell (importnat for renal excretion, intestinal absorption and drugs reaching their target site
-efflux transporters
what are the types of drug transporters?
intake and efflux
what are the different type of drug molecules
- polar molecules
-ions
-quaternary molecules
-ionizable molecules
-lipophilic molecules
what are the qualilties of a polar molecule?
water soluble
uneven charge BUT NO NET CHARGE
glucose, water, antibiotic
what are the qualities of an ion?
-electrons and protons are off balance
-have a net charge
-due to their charge, they cannot pass through the cell membrane - they can pass through pores if theyre small
what are the qualities of quaternary annomium compounds?
- always postive
-always have a nitrogen
-unable to pass directly through the cell membrane
desribe the qualities of an ionizable molecule
-can be charged or uncharged
-molecules are weak acids or weak bases
-determination of whether it will have a charge depends on the medium that its surrounded in
- weak acid + weak acid = non ionized
-weak base + weak base = non ionized
-weak base + weak acid = ionized!
Impact of pH on drug movement
-ionized drugs cannot pass through membrane
-most drugs are weak bases and therefore can pass
through the membrane into an alkaline medium
(non ionized drugs can pass)
why does ion trapping occur?
- occurs when there’s a difference in pH on different sides of the membrane
-drugs accumulate on one side when theyre ionized
-the cause of an overdose!!
how do hydrophilic drugs move out the capillaries?
-cannot penetrate the membrane
-must pass through fenestrATIONs to exit
how do lipophilic drugs pass out of the capillaries?
- passes through the endothelial cell membrane
-can also pass through fenestrations
Describe how drugs move out of the capillaries at the BBB?
- cells that line the endothelial cells in the brain are
called astrocytes
-THERE ARE NO FENESTRATIONS IN THESE
CAPILLAIRIES, THERE ARE ONLY TIGHT JUNCTIONS, THEREFORE HYDROPHILLIC CANNOT PASS THROUGH BUT LIPOPHILLIC CAN
