The various routes of drug delivery are considered to be novel like nasal, buccal, rectal, ocular, pulmonary and vaginal routes. They had been studied over the past 20 years as a substitute for oral and parenteral route. The parenteral route needs frequent injection as well as technical knowhow which limit its use.With respect to the oral route, their major advantage sis the circumvention of the hepatic first pass metabolism and of chemical and enzymatic degradations that generally occur in stomach. Therefore mucosal drug delivery system has advantage over it.