Rifampicin binds to the DNA dependent RNA polymerase. This binding causes a conformational change in the polymerase thereby inhibiting synthesis of new RNA. After absorption from the GI tract, the drug is eliminated via the bile. In general, rifampicin is well tolerated and can cause side effects like rash, fever, nausea and vomiting.

Since rifampicin is a potent inducer of hepatic microsomal enzymes, it can lead to decreased half-lives of drugs, which are metabolised by these enzymes. Rifampicin is used in the treatment of tuberculosis and as adjunctive therapy for the treatment of Gram-positive infections with penicillinase activity.


Rifampicin is an important drug in leprosy therapy.


Like rifampicin, isoniazide and pyrazinamide are important drugs in the treatment of tuberculosis.