Comparison of serum phenytoin levels in epileptic patients who swallowed their phenytoin tablets with or without previous chewing.

This cross-over study was conducted to compare serum phenytoin levels after chronic ingestion of phenytoin tablets with or without previous chewing. The phenytoin therapy was administered as 50 mg chewable Infatabs tablets in a single morning dose of 200 mg. There was no significant difference between the two modes of ingestion as regards serum phenytoin levels measured at various times after ingestion of the phenytoin tablets. Moreover, the area under the curve did not differ significantly during the 24 h interval. Minor changes between two Dilantin formulations, however, could influence drug availability.