What is rifampicin ?

Rifampicin or rifampin is a bactericidal antibiotic drug of the rifamycin group.It is a semisynthetic compound derived from Amycolatopsis rifamycinica.Rifampicin was introduced in 1967, as a major addition to the cocktail-drug treatment of tuberculosis and inactive meningitis, along with isoniazid, ethambutol, pyrazinamide and streptomycin. Rifampicin is an intensely red solid, and the small fraction which reaches body fluids is known for imparting a harmless red-orange color to the urine  of users, for a few hours after a dose. Maximal concentrations in the blood are decreased by about a third when the antibiotic is taken with food.
Rifampicin was introduced in 1967, as a major addition to the cocktail-drug treatment of tuberculosis and inactive meningitis, along with pyrazinamide, isoniazid, ethambutol and streptomycin ("PIERS"). It requires a prescription in North America. It must be administered regularly daily for several months without break; otherwise, the risk of drug-resistant tuberculosis is greatly increased. In fact, this is the primary reason it is used in tandem with the three aforementioned drugs, particularly isoniazid. This is also the primary motivation behind directly observed therapy for tuberculosis.
Rifampicin resistance develops quickly during treatment, so monotherapy should not be used to treat these infections — it should be used in combination with other antibiotics.Rifampicin is typically used to treat Mycobacterium infections, including tuberculosis and Hansen's disease. It can be used to treat abscesses, as an uncommon complication of BCG vaccination for tuberculosis.[citation needed]
There is no difference between a three to four month regimen of rifampicin and a six to nine month regimen for preventing active tuberculosis in those with HIV-negative latent tuberculosis. The quality of the evidence was however low.
With multidrug therapy used as the standard treatment of Hansen's disease, rifampicin is always used in combination with dapsone and clofazimine to avoid eliciting drug resistance.