Mhaske DB, Sreedharan S and Mahadik KR
Bioenhancers can be defined as chemical entities, which when mixed with drugs promote and augment their bioavailability without showing any synergistic effect with the drug. The factors like toxicity, cost, poor bioavailability and long term administration of drugs give rise to the need of bioenhancers which help overcome most of these problems. Piper species produce a pungent alkaloid named Piperine or 1-peperoyl piperidine. Piperine increases permeability at the site of absorption by modulating lipid environment and membrane dynamics. Piperine has a molecular structure that is suitable for enzyme inhibition. It augments the bioavailability of several drugs like carbamazepine, curcumin, ciprofloxacin, ampicillin, metronidazole, oxytetracycline and many others by inhibiting various metabolizing enzymes. Thus piperine, being an efficacious inhibitor of drug metabolism is a powerful enhancer of absorption. The following review explores the mechanism, metabolism inhibition, influence of structural changes on activity, and drugs bioenhanced by piperine. It provides an insight on the application of piperine as an effective bioenhancer and the superiority of a bioenhanced drug formulation over the one without a bioenhancer. This concept which is found to be beneficial, has its roots in Ayurveda-the traditional Indian system of medicine and has been applied to various drugs. It presents a fine instance of the advantage of amalgamating a traditional system with contemporary medicine.