Antimycobacterial drugs Flashcards
Treat M. avium-intracellulare?
Azithromycin
Rifampin
Ethambutol
Streptomycin
Treat M. leprae?
Dapsone Rifampin (Dapsone & Rifampin alone = Tuberculoid form) Clofazimine (add if lepromatous form)
Clinical use of Isoniazid?
Mycobacterium tuberculosis
solo prophylaxis against MTB.
Pyrazinimide MOA?
inhibits mycolic acid production by blocking mycobacterial fatty acid synthase I
effective in acidic pH of phagolysosomes- where TB engulfed by macrophages is found
clinical use of pyrazinimide?
Mycobacterium tuberculosis
Toxicity of pyrazinamide?
hyperuricemia
hepatotoxicity
MOA of Isoniazid (INH)?
dec synthesis of mycolic acids
bacteria catalase-peroxidase (KatG) needed to convert INH to active metabolite
MOA of Ethambutol?
dec carbohydrate polymerization of mycobacterium cell wall by blocking arabinosyltransferase
Toxicity of Isoniazid?
Neurotoxicity
Hepatotoxitiy
Lupus
Pyridoxine (Vit B6) may prevent neurotox & lupus, INH may deplete B6.
*INH = Injures Neurons & Hepatocytes
clinical use of ethambutol?
Mycobacterium tuberculosis
toxicity of ethambutol?
optic neuropathy (red green color blindness)
Treat M. tuberculosis?
Rifampin Isoniazid Pyrazinamide Ethambutol (RIPE)
M. leprae prophylaxis?
None
M. avium-intracellulare prophylaxis?
Azithromycin
M. tuberculosis prophylaxis?
Isoniazid
MOA of Rifampin?
inhibits DNA-depended RNA polymerase
inhibits mRNA synthesis
Toxicity of Rifampin?
hepatotoxity drug interactions (inc p-450) = dec drug orange body fluids
user of rifampin?
Mycobacterium tuberculsis
Leprosy (delays dapsone resistance)
meningococcaal prophylaxis & HiB prophylaxis as monotherapy.
4 R’s of Rifampin
RNA pol inhibitor
Revs up P-450
Red/Orange body fluids
Rapid resistance used alone
