General pharma

Phase 2 metabolism

Conjugation reactions in which a polar molecule is linked to a suitable functional group on a drug or one of its Phase 1 metabolites. morphine-6-glucorinde much more potent, fluoxetine TO S-norfluoxentine 10 day half life

enteric coated for drugs

Omeprazole, lansoprazole

vancomycin given which way for clostridium difficile

Oral, not absorbed via small intestines, goes to colon

Phase 1 metabolism

Oxidation, reduction, hydrolysis

Distribution phase

The phase of drug movement from the site of administration into the tissues, factors are CO, capillary permeability, binding to plasma protein, lipophilicity

first order

constant fraction of the drug is eliminated per unit of time

Vd

defined as the fluid volume that is required to contain the entire drug in the body at the same concentration measured in the plasma

effect of Vd of drug half-life

delivery of drug to organs of elimination depends not only on blood flow but also on the fraction of the drug in the plasma, very large Vd most of the drug is in extrplasmic space and unavailable to reach excretory organs, factor increasing Vd can increase half-life and duration of action of the drug .

inhibitor of CYP

ketoconazole, omeprazole, erythromycin, Ritonavir

highest bioavailability routes

parental route

CYP2C9/10 inducers

phenobarbital , rifampin

Inducers of CYP3a4/5

phenobarbital, phenytoin rifampin, dexamethasone carbamazepine, st,jOHNS WART

P-glycoprotien

pump drugs out of cell, reduces drug absorption, multi drug resistance, melanoma

bioavailability

rate and extent to which a drug reaches the systemic circulation, Iv 100%, AUC (AREA under the curve)

the pKa is a measure of

the strength of the interaction of a compound with a proton, the lower the ... the more acidic, higher the ...more basic

A drug passes if its more readily ..

uncharged, non ionised

Drug clearance

hepatic metabolism, biliary and renal, (lung excretion)

zero order kinetics

few drugs, aspirin, ethanol, phenytoin, doses are very large, therefore C is much greater than Km and velocity equation becomes Vmax*{c}/C =Vmax