TB Pharm Ex 3 Flashcards
TB first line drugs
isoniazid * Rifampin* pyrazinamide* Ethambutol* Streptomycin Rifabutin * must be used in combination for active disease
TB second line drugs
Cycloserine p-aminosalicylic acid ethoinamide amikacin/kanamycin capreomycin Flouroquinolones
what is active TB always treated with?
Isoniazid, Rifampin, Ethambutol, pyrazinamide
- reduces resistance and significant reduces tansmission rates
isoniazid mechanism
inhibits the synthesis of mycolic acid in the mebrane
- requires KAT G in the host to be active
Isoniazid uses
Active- +RIF,EMB, PZA
Latent-monotherapy
Prophylaxis- causes liver damage
Isoniazid toxity
Hepatitis- esp older adults and fast acetylators
Peripheral nephritis- in slow acetylators
Hemolysis in G6PD
Drug induced lupus
Rifampin mechanism
inhibits DNA dependent RNA polymerase
Rifampin uses
- Active
- Latent
+ leprocy, G+, some G-, chlamydia, and Pox virus
Rifampin effects
Hepatic Enzyme induction: inducer of p450s (increase metabolism of many endogenous substances)
- not recomended for HIV treated individuals
- decreases effectiveness of birth control
- orange body fluids
Ethambutol mech
inhibits arabinosyl transferases involved in the synthesis of arabinogalactan
STATIC
Ethambutol Pharmkinetics
good CNS distribution
renal elimination and feces/ urine
Ethambutol Toxicities
decrease visual acuity and loss of green red perceptions
* not recommended for <13*
Pyrazinamide
Mech: unknown -best at acidic PH > good for tb within macrophages -bests for dormant organisms - excreted in urine Toxic: hepatic disfunction
Streptomycin
Aminoglycosides 30 s cidal -best for extracellular Mtb renal excretion toxic: ototoxic and nephrotoxic MDR and XDR intrest
Ritabutin
Oral inhibits DNA dep RNA pol -replaces rifampin in HIV TB coinfected patients - becuase less potent inducer of P450 orange color
