Can Compazine be used when using phenytoin?

It is best to avoid taking Compazine (prochlorperazine - a phenothiazine) and phenytoin together as Compazine may increase phenytoin levels and the effect of the phenothiazine may be decreased.

If it is necessary for these to be given together then close monitoring of clinical and laboratory evidence of phenytoin toxicity is indicated. Patients should be advised to notify their physician if they experience symptoms of possible hydantoin toxicity, including drowsiness, visual disturbances, change in mental status, seizures, nausea, or ataxia.

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