Vol. 8, Issue 3 (2019)

Author(s):
Abdul Mannan and Fatima Unnisa

Abstract:
Biotransformation means chemical alteration of chemicals such as xenobiotics, nutrients, toxins and drugs in the body Biotransformation of xenobiotics can dominate toxicokinetics and the metabolites may reach higher concentrations in organisms than their parent compounds. The metabolism of a drug or toxin in a body is an example of a biotransformation Drugs can undergo one of four potential biotransformation: Active Drug to Inactive Metabolite, Active Drug to Active Metabolite, Inactive Drug to Active Metabolite, Active Drug to Toxic Metabolite Drug metabolism involves the enzymatic conversion of therapeutically important chemical species to a new molecule inside the human body. The process may result in pharmacologically active, inactive, or toxic metabolite. (Biodetoxification) presystemic metabolism occurs when an orally administered drug undergoes biotransformation into different metabolites by the biochemicals such as cyp450, hormones and the other factors such as genetic variation, nutrition exposure to environment and leads to decreases the oral bioavailability and absorption of the drugs. All the drugs given by oral route undergoes a first pass metabolism either in the gut or the liver, while some of the drugs gets destroyed before they reach into a systemic circulation. In this article we review how the various Strategies such as the SEDDS CDEPT prodrugs and other routes eventually helps in elimination of the first pass effect of orally administered drugs and enhancing the oral bioavailability of drugs.