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PHENYTOIN AND TRICYCLICS

Medical Diagnosis and Drugs, Medications
Some very limited evidence suggests that imipramine can raise serum phenytoin levels. Phenytoin possibly reduces serum desipramine levels. Fosphenytoin, a prodrug of phenytoin, may interact similarly.
Care should be taken if deciding to use this combination in epileptic patients. If concurrent use is undertaken the effects should be very well monitored. Note that the tricyclics lower the convulsive threshold.
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