MAOI reversibility and selectivity

Drug Reversible inhibition Enzyme selectivity Indication 

MAOI=monoamine oxidase inhibitor MAO=monoamine oxidase. Selective at lower doses, nonselective at higher doses. 

Another important characteristic of M AOIs is the production of reversible versus irreversible enzyme inhibition. An irreversible inhibitor permanently disables the enzyme. This means that MAO must be resynthesized, in the absence of the drug, before the activity of the enzyme can be reestablished. Resynthesis of the enzyme may take up to 2 weeks. For this reason, an interval of 10-14 days is required after discontinuing irreversible inhibitors and before instituting treatment with other antidepressants or permitting the use of contraindicated drugs or the consumption of contraindicated foods. On the other hand, a reversible inhibitor can move away from the active site of the enzyme, making the enzyme available to metabo-hze other substances. The reversibility and selectivity of the currently available MAOIs are summarized in Table 2-4. 

More so than with other medications, it is imperative to review the patient s medical status and current medications before pre- 

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