Hepatic drug-metabolizing enzyme system

Cheadwick RW, Copeland MF, Carlson GP, et al. 1988. Comparison of in vitro methods for assessing the effects of carbon tetrachloride on the hepatic drug-metabolizing enzyme system. Toxicol Lett 42 309-316. 

Interactions involving changes in the activity of hepatic drug-metabolizing enzyme systems have been discussed (see also Chapters 4 and 66). 

Rifamycin is found to afford induction of the specific hepatic drug-metabolizing enzyme system and, therefore, accelerates the metabolism of digitoxin, methadone, phenytoin, 3-blockers, verapamil, oral contraceptives, chloramphenicol, theophylline, besides—oral anticoagulants, estrogens, tolbutamide, barbiturates and itself... 

Dalvi RR, Dalvi PS (1991) Differences in the effects of pipeline and piperonyl butoxide on hepatic drug-metabolizing enzyme system in rats. Drug Oiem Toxicol 14 219-229... 

The hepatic and renal toxicities of chloroform are selectively modified by induction of the drug-metabolizing enzyme systems in those organs (ref. 39) and the production of phosgene is strongly indicated (ref. 40). 

Kluwe, W.M., K.M. McCormack and J.B. Hook, "Selective Modification of Renal and Hepatic Toxicities of Chloroform by Induction of Drug-Metabolizing Enzyme Systems in Kidney... 

The liver is the principal site of drug metabolism. Hepatic drug metabolism is usually classified into two distinct phases. Phase I reactions are oxidation, reduction or hydrolysis. One of the most important systems that catalyse oxidation are the haem-containing cytochrome P-450 enzymes. 

Induction of hepatic microsomal drug metabolizing enzymes. Additive central nervous system depression with other central nervous system depressants. 

Absorption and metabolism Carbamazepine is absorbed slowly following oral administration. It enters the brain rapidly because of its high lipid solubility. Carbamazepine induces the drug metabolizing enzymes in the liver, and its half-life therefore decreases with chronic administration. The enhanced hepatic P-450 system activity also increases the metabolism of other antiepileptic drugs. 

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