Abstract

In vivo pharmacokinetic studies of N-Mannich base derivatives of ibuprofenamide as prodrugs were performed on rabbits. Ibuprofen and both the prodrugs (IBMB-M and IBMB-P) were administered orally and at different time intervals blood samples were collected and assayed for ibuprofen and ibuprofenamide by HPLC method. From the plasma concentration-time profile; (C p ) max , t max , AUC and the time required to achieve minimum effective concentration were calculated. N-Mannich base prodrugs first get hydrolyzed to ibuprofenamide which in turn gets hydrolyzed to ibuprofen by the enzyme amidase. The (C p ) max and AUC values of IBMB-M were found to be more compared to IBMB-P. In both the cases ibuprofen started appearing after 2 h and it required minimum 4 h to get the ibuprofen in therapeutic range. Both the prodrugs released ibuprofen slowly which gave sustained effect. IBMB-M provided ibuprofen in therapeutic range for 48 h and IBMB-P for 24 h.