Antimycobacterial Drugs Flashcards
What drug is used as prophylaxis against M. tuberculosis?
Isoniazid
What drug is used as prophylaxis against M. avium?
Azithromycin
Rifabutin
What is the treatment of M. tuberculosis?
Rifampin
Isoniazid
Pyrazinamide
Ethambutol
What is the treatment of M. avium?
Azithromycin or clarithromycin
Ethambutol
(can add rifabutin or ciprofloxacin)
What is the treatment of M. leprae?
Dapsone
Rifampin
(Tuberculoid form)
+ clofazimine for lepromatous form
What is the MOA of action of rifampin/rifabutin?
Inhibit DNA-dependent RNA polymerase
What effect do rifampin/rifabutin have on the CYP450 system?
Activators
What rifamycin drug is favored in patients with HIV infection and why?
Rifabutin because it stimulates CYP450 system less than Rifampin
Should rifampin/rifabutin be used as monotherapy?
No- rapid resistance
What effect can rifamycins have on body fluids?
Turn them red/orange
What is the MOA of isoniazid?
Decrease synthesis of mycolic acids
What is required to activate isoniazid?
Bacterial catalase-peroxidase
How can bacteria require resistance to isoniazid?
Mutations leading to underexpression of KatG
What toxicities are assoicated with isoniazid?
Neurotoxicity
Hepatotoxicity
What can be given with isoniazid to prevent neurotoxicity?
Pyridoxine (vitamin B6)
What is the MOA of pyrazinamide?
Uncertain
What is the active form of pyrazinamide?
Pyrazinoic acid
What toxicities are associated with pyrazinamide?
Hyperuricemia
Hepatotoxicity
What drug used to treat M. tuberculosis can cause optic neuropathy leading to red-green color blindness?
Ethambutol
What is the MOA of ethambutol?
Block arabinosyl transferase
Decreases carbohydrate polymerization of mycobacterium cell wall
What antimycobacterial drug is given IV?
Streptomycin
What is the MOA of streptomycin?
Protein synthesis inhibition
Binds 30s ribosomal subunit
