Anti-TB Flashcards
Rifampicin - MOA
Both rapidly growing & slow/intermediate-growing bacilli
Block DNA-dept RNA polymerase
Rifampicin - Resistance
Mutation in gene encoding RNA polymerase B chain
Rifampicin - Clinical
Active, Latent TB, Leprosy
Rifampicin - PK
Good oral
Good CSF
What RoA for RIPE?
Oral
Can RIPE be used in BOTH breastfeeding & pregnancy?
Yes
Rifampicin use in pregnancy required to give _ to _ as well
Vitamin K, Neonates
Rifampicin - DDI
MAJOR DDIs CYP inducer: - Warfarin - Corticosteroids - Hormonal contraceptives - HIV protease inhibitors
Rifampicin - SE
Cutaneous synd Flu-like synd Resp synd Hepatitis Orange discoloration of body fluids
Isoniazid - MOA
Rapidly growing bacilli
Prodrug -> catalase peroxidase -> free radicals -> inhibit mycolic acid formation -> cell wall
Isoniazid - Resistance
Mutations to:
1) Catalase peroxidase
2) Regulatory genes involved in mycolic acid synthesis
Isoniazid - Clinical
Active, Latent TB, Prophylaxis
Isoniazid - PK
Good oral Good CSF Metabolism via N-acetyltransferase: - Rapid = half-life 1hr (eg. Chinese) - Slow = half-life 2-5hr (eg. Indian)
Isoniazid - Metabolism pathway
Isoniazid itself not toxic; only its metabolite Hydrazine is
2 pathways:
1) N-acetyltransferase 2 (NAT 2) pathway = Acetyl hydrazine
2) Amidase pathway = Hydrazine
Isoniazid in pregnancy - both _ & _ should receive _
Mother, Baby, Pyridoxine supplement (to prevent B6 deficiency)
