Issar- Drug Absorption Flashcards
is drug absorption rate in the GI tract greater in the stomach or intestine?
intestine
diseases can affect the absorption of drugs. in a patient with congestive heart failure how is splanchnic blood flow affected?
its reduced and can develop edema in the bowls of patient (harder to absorb drug since motility is being decreased)
how might anti-cholinergic drugs (antidepressants) affect drug absorption in the gut?
the anti-cholinergic side effects cause slower peristalsis in the GI tract (slower stomach emptying may delay drug absorption)
what is micronization?
increasing the surface area of a particle (drug) to increase the drug dissolution
what part of the GI tract is more likely to absorb the a drug that is weakly acidic?
in the intestine because the pH in the intestine is higher.
what physicochemical factors affect drug absorption?
drug lipophilicity; polymorphic crystals/solvents; drug solubility and pH; particle size
what routes of administration lack a “First Pass Effect”?
Parenteral, Topical/transdermal/inhaled, sublingual and buccal
list the pharmacokinetic pathways.
liberation, absorption, excretion, metabolism and distribution
what type of drug would you not administer intravenously?
insoluble drugs or oils
are irritating drugs allowed to be administered subcutaneously?
nope. it would be painful and lead to necrosis of that tissue
how would you inject large amounts of irritating drugs?
intramuscular injection
although drugs injected in the intramuscular region absorb relatively fast; what factors can be altered to slow or speed up absorption?
vascularity, ionization, and lipid solubility of the drug. Volume of injection and the osmolarity of the solution.
what is the dissolution rate of small drugs taken buccally?
slow
what are the ideal properties of a drug that should be administered sublingual?
non-ionized, highly lipid soluble, rapid dissolution
are weak acids or weak bases more readily absorbed in the stomach?
weak acids
