Drug metabolism chloral hydrate

Several other drugs, eg, metronidazole, certain cephalosporins, sulfonylurea hypoglycemic drugs, and chloral hydrate, have disulfiram-like effects on ethanol metabolism. Patients should be warned to avoid drinking ethanol while taking these drugs and for several days after they discontinue them. 

Metabolism converts a lipophilic molecule into a more hydrophilic (water-loving) metabolite that can be excreted in urine by the kidneys. In the majority of cases the drug is detoxified, or made pharmacologically inactive by this metabolic breakdown. However, a few drugs need to be metabolised to become psychoactive for instance, the sedative-hypnotic chloral hydrate is converted to the active metabolite trichloroethanol. In this case the parent molecule is referred to as a prodrug. With many drugs, both the parent compound and its metabolites are psychoactive. An example of this is the tricyclic antidepressant imipramine which is metabolised to desipramine, with... 

Oxidative reactions catalysed by non-microsomal enzymes are less varied than those mediated by cytochrome P450 mono-oxygenases but are important in the metabolism of some drugs (e.g. isoproterenol, methylxanthines, methimazole, ethanol, chloral hydrate), endogenous substances (adrenalin, histamine) and naturally occurring compounds (vitamin A). Theophylline and caffeine (methylxanthines) simultaneously undergo microsomal cytochrome... 

Other adverse effects Barbiturates and carbamates (but not benzodiazepines, buspirone, zolpidem, or zaleplon) induce the formation of the liver microsomal enzymes that metabolize dmgs. This enzyme induction may lead to multiple drug interactions. Barbiturates may also precipitate acute intermittent porphyria in susceptible patients. Chloral hydrate may displace coumarins from plasma protein binding sites and increase anticoagulant effects. 

C. Drugs or chemicals metabolized by alcohol dehydrogenase (eg, chloral hydrate, isopropyl alcohol) will also have impaired elimination. Fomepizole and ethanol mutually inhibit the metabolism of each other. 

Among drugs introduced in the nineteenth century, chloral hydrate (3.21) is reduced in the body to trichloroethanol (3.22) which is also hypnotic (Butler, 1948) and acetanilide (3.23) and phenacetin 3.24) acts as analgesics after metabolism to p-acetamidophenol (3,6) which has now replaced these pro-drugs (Brodie and Axelrod, 1948, 1949). An old suggestion that codeine exerts some of its analgesic effect after demethyla-tion to morphine has been confirmed (Adler, 1963). 

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