Study of Anticonvulsant Drug (Phenytoin) Along with Synthesis and Pharmacological Effect

Abstract

Phenytoin is slowly but nearly completely absorbed in the small intestine; oral bioavailability ranges from 70 to 100%. The drug is widely distributed in the body and is almost completely protein-bound, primarily to albumin. Phenytoin is metabolized primarily in the liver by CYP2C9 and CYP2C19 to 5-(4-hydroxyphenyl)-5-phenylhydantoin, which is glucuronidated and excreted. Minor metabolites that are produced include 3,4-dihydrodiol, catechol (3,4-dihyroxyphenyl-phenylhydantoin), and 3-O-methylated catechol. Since hepatic metabolism is a saturable process, small increases in dosage can result in very large increases in serum levels. CYP2C9 also metabolizes warfarin and tolbutamide, which may explain interactions between phenytoin and these drugs. Phenytoin and metabolites may undergo enterohepatic recirculation prior to excretion. Most of the drug is eliminated in the urine as inactive conjugated metabolites, but small amounts of the unchanged drug may be present in the urine (2–4%) and feces (5%). In this study we prepared Phenytoin from Benzil and urea and determined it percentage yield. Keywords: Phenytoin, Benzil, Urea, Percentage yield