 Leprosy is still a common medical problem in many countries including Bangladesh, and currently there are at least 3500 leprosy patients in this country at risk of ENL reaction, which is a distressing complication of Multibacillary MB leprosy liable to result in permanent disability if not well treated. The drug of choice is either prednisolone which often causes adverse effects especially with prolonged use or thalidomide which is not available in Bangladesh.Clofazimine in high doses is recommended as an alternative but supplies are difficult to obtain. Hence the need for an alternative drug which could be used as a steroid sparing agent or an alternative to steroids in ENL reaction. Montelukast is a leukotriene inhibitor already available on the open market in this country as an immunomodulator, and a small clinical trial with zafirlukast very similar drug suggested that drugs in this group may be effective for ENL. 