MT1 Flashcards
Volume of Distribution (Vd)
Vd = dose of drug / measured conc.
Half Life
t1/2 = (0.693*Vd) / CL (clearance)
Factors affecting Distribution
- organ blood flow
- molecular size ex. heparin
- lipid solubility (*brain)
- plasma protein binding (10-99%)
Metabolism
Liver via 2 processes:
Phase 1: Biotransformation
*oxidative / reductive / hydrolytic rxns –> P450 (CYP) monooxygenase system
Phase 2: conjugation rxns –> liver enzymes
Metabolism Phase II
commonly added molecules
- glucuronic acid
- sulfate
- carboxylic acid
Excretion (kidney - renal)
- passive glomerular filtration
- active tubular secretion
- passive tubular reabsorption (urine pH is key)
Excretion (bile)
Liver –> intestine via common bile duct
- larger drugs
- conjugated metabolites
(carrier mediated process)
Viral Replication
APURAR
Covid-19 virus
- ssRNA
- 125nm diamter
- genomic proofreading mech.
RDRP inhibitors
- remdesivir
- ribavirin
- favipiravir
MOA: RDV-TP resembles ATP and competes w the nucleotide during viral RNA synth. RDV-TP forms phosphodiester bond w next nucleotide
MIC vs MBC
MIC: lowest conc. of antibiotic that inhibits visible growth of a microorganism after overnight incubation
MBC: min bacteriocidal conc.
MBC:MIC
- less than or equal to 4 is bacteriocidal
- over 4 is bacteriostatic
b- lactam antibiotics
Penicillin
MOA: inhibits synth of bacterial PG cell wall
Macrolides (antibiotic)
Azithromycin (product of actinomycetes)
MOA: inhibits bacterial protein synth by binding reversibly to 50S ribosomal subunit
Aminoglycosides (antimicrobial)
Gentamicin
MOA:
- interferes w bacterial protein synth by irreversibly binding 30 and 50S subunits
- creates fissures in outer membranes of bacteria
Tetracyclines (antimicrobial)
Doxycycline
MOA:
- inhibits bacterial protein synth by binding REVERSIBLY to 30S subunit (and possibly 50S)
- cause changes in cytoplasmic membrane