ORAL GABAPENTIN DISPOSITION IN PATIENTS WITH EPILEPSY AFTER A HIGH-PROTEIN MEAL

Purpose: To study the interaction between gabapentin (GBP) and high-pr otein meals, 12 patients with epilepsy were administered this drug bot h while in a fasting state and after a high-protein meal. Methods: Aft er having acquired their informed consent, the patients (suffering fro m partial complex seizures resistant to other anticonvulsants) were ra ndomly assigned to 2 groups of 6 subjects. Each subject was treated in a fasting state with a single 400 (group A) or 800 (group B) mg GBP o ral dose. After 24 h, the GBP dose regimen was repeated, but was given after a high-protein meal. Serum GBP concentrations were measured by LC-Mass at baseline and 0.5, 1, 2, 3, 5, 7, 9, 12, and 24 h. Saliva GB P concentrations were determined at baseline and 2, 4, 8, and 12 h. GB P urinary excretion was determined at 0-4, 4-8, and 8-12 h intervals. The following kinetic parameters were calculated: area under the conce ntration time curve from zero time to 24 h after the dose, AUC 0-24 h; maximal serum concentration, C-max; time to the maximal serum concent ration, T-max; absorption rate constant, ka; elimination rate constant , beta; elimination half-time, t1/2 beta. Student's t test for paired data, with significance assigned at P < 0.05, was used. Results: No st atistically significant differences were seen in GBP serum or saliva c oncentrations or in its urinary excretion (both in A or B group) betwe en fasting and after the high-protein meal. Conclusions: High-protein meals do not seem to interfere with oral disposition of GBP.