Alkyl ester prodrugs for improved topical delivery of ibuprofen

Topical delivery of ibuprofen directly to the site of inflammation can overcome gastrointestinal side effects associated with its long term oral administration. The set of physicochemical properties necessary for optimum topical delivery of ibuprofen can be imparted by formation of its ester prodrugs. Various alkyl ester prodrugs (methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-buty, n-pentyl, hexyl, heptyl, octyl, lauryl, cetyl and octadecyl esters) were synthesised and studied for their physicochemical properties and activity in the carrageenan induced rat paw oedema by topical route. Favourable shift in lipophilicity and self penetration enhancing effect of prodrugs responded in improved topical activity over the parent drug ibuprofen.