Nature and Stability of Reactive Metabolites

Oxidation Cytochrome P450s Prostaglandin synthetase Flavin-containing monooxygenases Alcohol and aldehyde dehydrogenases 

As a result of their high reactivity, reactive metabolites are often considered to be short-lived. This is not always true, however, because reactive intermediates can be transported from one tissue to another, where they may exert their deleterious effects. Thus reactive intermediates can be divided into several categories depending on their half-life under physiological conditions and how far they may be transported from the site of activation. 

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