Main SE of 4 TB drugs:
RIFAMPICIN: orange secretions, acute renal failure, pruritis, flu-like syndrome with infrequent dosing, thrombocytopenia, haemolytic anaemia. enzyme inducer therefore increases elimination of warfarin, phenytoin, pill, antiretrovirals, ketoconazole, chloramphenicol, methodone.
ISONIAZID: hepatotoxic (reduce dose for liver failure. signs of hepatoxicity include nausea, vomiting, abdo pain, fever, rash) peripheral neuropathy (give B6 ie. pyridoxine if DM, pregnant, alcoholic etc) increases blood level and toxicity of phenytoin.
ETHAMBUTOL: dec visual acuity, optic neuritis.
PYRAZINAMIDE: hepatotoxicity, arthralgia, GI upset, rash, hyperuricaemia.