Pharm--TB Drugs Flashcards
Isoniazid MOA
Inhibit cell wall synthesis - mycolic acid synthesis; cidal for rapid dividers and static for slow growing
Works for intracellular bc penetrates host cells
Never use INH as a single agent in ACTIVE TB.
Ethambutol MOA
Inhibit cell wall synthesis - disrupts arabinogalactan synthesis
Pyrazinamide MOA
Disrupts PM and energy metabolism - conversion to metabolite decreases cell pH
Rifampin
Inhibit RNA synthesis by binding RNA pol
Thinking of INH ADME, you worry about…
Chronic liver disease - needs dose reduction
INH AEs
Peripheral neuropathy; hepatotoxicity (2%) due to toxic metabolite
INH interactions
Antacids with Al; inhibitor of P450
INH supplement with what and why
Vit. B6 to prevent peripheral neuropathy
Rifampin cidal static?
Cidal
Rifampin excretion
bile
Rifampin AEs
Makes body fluids orange-red
Hepatotoxic
Induces P450
What are some other uses for rifampin besides TB?
MRSA, meningitis prophyl from H flu; staph in carriers
Antileprosy
Ethambutol cidal static?
Concentration dep
Ethambutol ADME note
reduce dose in renal disease
Ethambutol AE
Loss of color discrimination (optic neuritis) - dose related
Hyperuricemia
Ethambutol interactions
Al+ antacids
Pyrazinamide cidal static?
dep on conc
This one is a prodrug
pyrazinamide
Pyrazinamide AEs
Dose-related hepatotoxicity - cumulative
Hyperuricemia
Arthralgia
Cycloserine MOA
Block cell wall synthesis / structural analog of D-Ala
Cycloserine ADME ..
Dose adjustment for renal
Cycloserine AEs
CNS - HA, tremor, confusion, psychosis and suicidal tendencies, seizures
Cycloserine C/I
seizures
What drugs are used for XDR?
FQs, and at least one of: amikacin, kanamycin, or capreomycin
