RAPID CONVERSION FROM ONE MONOAMINE-OXIDASE INHIBITOR TO ANOTHER

Background: Numerous sources state that switching from one monoamine o xidase (MAO) inhibitor to another can be done only after a 14-day wash out period. Ln hospitalized patients and severely depressed outpatient s, such a wait may be impracticable. Method: We reviewed the case hist ories of eight consecutive and random patients whom we converted from one MAO inhibitor to another within less than the recommended waiting period. Results: Only one patient experienced troubling adverse effect s, and these effects were brief and time-limited. The patient's sympto ms were indicative of either withdrawal from tranylcypromine or a mild serotonin syndrome. All other patients tolerated the conversion well with minimal or no adverse effects. Four of the eight patients eventua lly responded to the new MAO inhibitor. Conclusion: These results sugg est that some patients can be cautiously but rapidly switched from one MAO inhibitor to another without prolonged drug-free periods. Unquest ionably, this strategy should be used only when the clinical picture m andates a rapid conversion. Further, it should be reserved for those p atients with established high compliance and should include close moni toring and the use of a low-tyramine diet. Extreme caution must still be undertaken in utilizing this approach until larger studies more acc urately determine the frequency of serious adverse effects.