Pharmacology Flashcards
biochemical factors that improve absorption
lmw
lipid soluble
non ionized
pinocytosis
energy dependent
compounds engulfed and packaged by cells
Vd =
total amount of drug in body (mg) / [(plasma concentration of drug (mg/L) x weight (kg)]
preterm vs full term in regards to Vd
preterm higher Vd
what do acidic and basic drugs bind to
acidic - albumin
basic - alpha-glycoproteins and lipoproteins
phase 1 reactions
- oxidation
- reduction
- hydrolysis
- demethylation
enzyme not specific for substrate
phase 2 reactions
conjugation of drug with endogenous component (glycine, glucuronic acid, sufate, glutathione or hippurate)
glucoronidation most important
which common drugs undergo glucuronidation
morphine
tylenol
zero order excretion
constant amount per time regardless of concentration
half life dependent on dosage
drugs that are zero-order
aspirin
chloramphenicol
ethanol
diazepam
first order exretion
constant percentation of drug per time
half life is independent of dosage
equation for determining dose to achieve steady state
- dose 1 = x dose
- steadystate goal
drugs that are first order
- theophylline
- phenobarbital
loading dose calculation
Vd (L/kg) X Cp (mg/L) / (S x F)
Cp = plasma concentration (Cp desired = Cp current)
S = fraction of drug that is active
F = fraction of drug that is bioavailable
Assume S and F = 1 if not specified
rate of clearance between preterm and term
preterm is slower due to higher Vd