Preparation and in vivo evaluation of indomethacin loaded true nanoemulsions

Indomethacin, a potent nonsteroidal anti-inflammatory drug, has been used in the treatment of various kinds of pains, inflammation and arthritis. However, oral administration of indomethacin produces serious gastrointestinal adverse effects. Therefore the aim of the present investigation was to evaluate the anti-inflammatory effects, skin irritation, activation energy and histopathology of indomethacin from transdermally applied true nanoemulsion. The anti-inflammatory effects of true nanoemulsions were compared with marketed Indobene(Â) gel on carrageenan-induced paw edema in rats. Skin irritation tests were performed on Wistar rats for 14 days. The % inhibition value after 12 h application was significant for optimized formulation F6 (83) as compared to marketed Indobene(Â) gel (P<0.01). Results of skin irritation test indicated that developed true nanoemulsion is safe for human use. The significant decrease in activation energy (1.396 kcal/mol) for indomethacin across rat skin indicated that the stratum corneum lipid bilayers were significantly disrupted (P<0.05). From these results it was concluded that the developed nanoemulsion have great potential for transdermal application of indomethacin.