general pharm Flashcards
rifampin moa
inhibition of bacterial DNA dependent RNA polymerase
rifampin adverse effects
GI effects, rash, red-orange body fluids, cytopenia
isoniazid moa
inhibition of mycolic acid synthesis
isoniazid adverse effects
neurotoxicity (give vitamin B6/pyridoxine); hepatotoxicity
pyrazinamide moa
unclear
pyrazinamide adverse effects
hepatotoxicity, hyperuricemia
ethambutol moa
inhibition of arabinosyl transferase (interference w. mycobacterial peptidoglycan cell wall synthesis) — ineffective against organisms other than mycobacteria
ethambutol adverse effects
optic neuropathy
streptomycin is limited to use for treatment of…
- M. TB
- plague
- tularemia
because of widespread antibiotic resistance
streptomycin (aminoglycoside)
interferes w. 16s rRNA of the bacterial 30S ribosomal subunit (prevent bacterial protein synthesis)
aminoglycoside resistance
mutations of genes that encode ribosomal proteins–> modifications in the ribosomal binding sites for these drugs
- aminoglycoside-modifying enzymes (transferases)
- mutated porins
fluoroquinolones resistance
-structural alteration of enzymes involved in DNA winding-unwinding
fluoroquinolones moa
inhibition of bacterial enzymes
- DNA gyrase (topoisomerase II)
- topoisomerase IV
rifampin resistance
structural alteration of enzymes involved in RNA synthesis (DNA-dependent RNA polymerase)–> prevent transciption
isoniazid resistance
decreased activity of bacterial catalase peroxidase (req for INH to its active metabolite –> inhibit mycobacterial mycolic acid synthesis)
