Goudanavar Prakash , Ramarao Venkata.I, Hiremath Doddayya and Udupi Rajgopal
A reservoir type transdermal patch for delivery of ketorolac tromethamine (KT), a potent analgesic agent was studied. Studies were carried out to investigate the effect of permeation enhancers on the in vitro permeation of KT across rat skin. Films were prepared by using hydroxy propyl methyl cellulose (HPMC) and polyvinylalcohol (PVA) polymers by incorporating glycerine as plasticizers using solvent casting method. A total of fourteen formulations were prepared by using same drug polymer ratio of 1:1 and incorporated different terpenes and vegetable oils as permeation enhancers in same concentrations. The prepared systems released the drug in the following order: FP2 > FP3 > FH2 > FP5 > FH3 > FP4 > FH5 > FH4 > FH6 > FP6 > FH7 > FP7 > FH1 > FH1. The various permeation parameters such as enhancement ratio and percent of drug permeated were determined for all the formulations. The maximum percent of drug permeation was observed with PVA monolithic system containing 10% d-limonene. Permeation enhancement of KT with different enhancers followed the order: d-limonene > cineole > olive oil > menthol >linseed oil > sunflower oil. The in vitro release studies revealed that terpenes showed better permeation enhancement than vegetable oils and the release was sustained up to 24 h and it follows zero-order kinetics. All the films were found to be stable at 37°C and 45°C with respect to their physical parameters. A reservoir type transdermal patch for delivery of KT thus appears to be feasible of delivering KT across skin.
