Drugs used in tuberculosis and leprosy

Publisher Summary This chapter discusses several drugs used in tuberculosis (TB) and leprosy. Hepatotoxicity is the most important adverse effect of anti-tuberculous drug therapy. Isoniazid, rifampicin, and pyrazinamide are the main culprits. There is wide variability in the risk of hepatotoxic reactions reported from different parts of the world. Old age and the presence of hepatic dysfunction on baseline evaluation are the most consistent predictors of hepatotoxicity during anti-tuberculous therapy. Coadministration of rifampicin with repaglinide considerably lowers the concentration of repaglinide and alters its therapeutic effect in diabetes mellitus. Several reports of accidental poisoning with dapsone in children were reported. Poisoning with dapsone results in cyanosis caused by methemoglobinemia, vomiting, mental confusion, tachycardia, and dyspnea. It has been suggested that treatment with multiple doses of activated charcoal may be sufficient for less severely poisoned children (methemoglobin concentration below 30%) and that a single dose of methylene blue should be given to those with higher concentrations.