answers
Pharmacology ✅✅the study of drugs and their effect on life processes; fundamental
part of modern medicine; success in treating disease and saving lives
drug ✅✅substance that induces a functional change in an organism by chemical or
physical means
two halves of pharmacology ✅✅pharmacokinetics and pharmacodynamics
pharmacokinetics ✅✅what the body does to the drug: absorption, distribution,
biotransformation/metabolism, excretion
pharmacodynamics ✅✅what the drug does to the body: detailed mechanism of what
happens, binding (receptor/enzyme), signal transduction, physiological effect
pharmacokinetics and dynamics are all affected by... ✅✅chemical and physical
properties
dose of drug --> ... --> ✅✅drug concentration in target organ over time -->
mechanism and magnitude of drug effect
relationship of pharmacokinetics ✅✅dose of drug and drug concentration in target
organ over time
relationship of pharmacodynamics ✅✅drug concentration in target organ over time
and mechanisms and magnitude of drug effect
absorption ✅✅drug goes into circulation (usually across tissue membranes) for
transport to site of action
diffusion rate affected by ✅✅lipid solubility (lipophilicity), etc.
rate of absorption depends on ✅✅route of administration (oral/IV/IM/inhaled/etc.)
oral administration absorption ✅✅huge absorbing surface area (GI) but first-pass
effect in liver
distribution ✅✅from bloodstream into target tissue/organ
distribution affected by ✅✅blood flow, plasma binding, size of molecule, polarity,
solubility
, excretion and biotransformation are gernally ✅✅irreversible, both decrease [drug]
OWPC ✅✅(oil-water partition coefficient) = [drug]oil/[drug]water
factors that hinder diffusion across membranes ✅✅low partition coefficient, thick
barrier, small barrier surface, low concentration ratio
factors that facilitate diffusion across membranes ✅✅high partition coefficient, thin
barrier, large barrier surface, high concentration ratio
partition coefficient >>1 ✅✅lipophilic more in oil
partition coefficient --> 0 ✅✅lipophobic (hydrophobic)
OWPC affected by ✅✅charged group, H bonding (hydrophilic --> pH effects)
very low PC ✅✅hard to cross membranes
higher PC ✅✅easier to cross membranes
extremely high PC ✅✅may accumulate in lipids
transmembrane diffusion may be supported by ✅✅ion channels, carrier proteins,
endocytosis
absorption from intestine can cross ✅✅BBB and other membranes-even skin
why is intermediate PC preferred ✅✅drugs need to interact with both environment
types
ibuprofen ✅✅motrin, shorter acting (4hrs)
naproxen ✅✅aleve, longer acting (12hrs)
ibuprofen and naproxen similar groups ✅✅binds enzyme and inhibits
naproxen and ibuprofen ✅✅both are over the counter (OTC) NSAIDS
acetylcholine ✅✅R=H; nonselective action at receptors (muscarinic, nicotinic), rapidly
metabolized by AchE, orally inactive