<prompt> ATT causing orange coloured urine is:RifampicinIsoniazidStreptomycinPyrazinamide  <response>: R ifampin Rifampicin, R: It is a semisynthetic derivative of rifamycin B Adverse effects :The incidence of adverse effects is similar to INH. Hepatitis, a major adverse effect, generally occurs in patients with preexisting liver disease and is dose-related: development of jaundice requires discontinuation of the drug-then it is reversible. Other serious but rare reactions are: ;Respiratory syndrome;: breathlessness which may be associated with shock and collapse. Purpura, haemolysis, shock and renal failure. Minor reactions usually not requiring drug withdrawal and more common with intermittent regimens are: ;Cutaneous syndrome;: flushing, pruritus rash especially on face and scalp, redness and watering of eyes. ;Flu syndrome;: with chills, fever, headache, malaise and bone pain. ;Abdominal syndrome;: nausea, vomiting, abdominal cramps with or without diarrhoea. Urine and secretions may become orange-red but this is harmless. ESSENTIALS OF MEDICAL PHARMACOLOGY K.D.TRIPATHI SIXTH EDITION PAGE NO:741,742 