5. Primary and Secondary Drug Resistance in Leprosy

Current treatment for leprosy is based on standard MDT which consists of dapsone, rifampicin, and clofazamine (WHO 1982). However, other antibiotics like ofloxacin, minocycline are also administered to patients, if required. Prior to the introduction of MDT, dapsone monotherapy was used for treatment. Long term monotherapy with dapsone resulted in poor compliance, treatment failures and emergence of dapsone resistant strains of M.leprae (Guinto et al 1981, dela Cruz et al 1996) Between the 1960’s and 1970’s additional antimicrobial agents like rifampicin and clofazamine were introduced for the treatment of leprosy (Browne et al 1962, Levy et al 1976). Although rifampicin proved to be a powerful anti-leprosy drug, the use of rifampicin alone or with dapsone led to the emergence of rifampicin resistance isolates (Grosset et al 1989). In India MDT was introduced in 1983 to prevent the spread of drug-resistance. However, drug resistant strains of M. leprae continue to be reported from parts of the world.