The effect of sucralfate on the steady-state serum concentrations of phenytoin.

The effect of sucralfate on steady-state phenytoin concentrations was evaluated in 6 normal volunteers. The subjects took phenytoin at bedtime until steady-state was confirmed (8 to 9 days) and then took in addition sucralfate 1g four times daily for a further 7 days. Serum phenytoin concentrations were measured on days 1, 3, and 7 of sucralfate administration. Measured phenytoin concentrations were 10.9 +/- 3.0 mcg/ml and 11.0 +/- 3.1 mcg/ml before sucralfate and 10.8 +/- 3.1 mcg/ml, 11.4 +/- 3.2 mcg/ml, and 11.1 +/- 2.5 mcg/ml during sucralfate administration (p greater than 0.05; ANOVA). These results suggest there is not a significant drug interaction between sucralfate and phenytoin.