Gabix Drug Interactions

Phenytoin, Valproic Acid, Carbamazepine, Phenobarbitone and Felbamate: There is no interaction during the concomitant administration of gabapentin with these drugs. Gabapentin steady-state pharmacokinetics is similar for healthy subjects and patients with epilepsy receiving antiepileptic agents.
Morphine: Patients who require concomitant treatment with morphine may experience increases in gabapentin concentrations. Patients should be carefully observed for signs of CNS depression eg, somnolence and the dose of gabapentin or morphine should be reduced appropriately.
Antacid: Gabapentin's bioavailability was reduced by up to 24% when co-administered at the same time with an aluminum- and magnesium-containing antacid. It is recommended that gabapentin be taken about 2 hrs following any such antacid administration.
Cimetidine: Cimetidine may increase serum concentration of gabapentin by decreasing its clearance by 14%.
Oral Contraceptives: Co-administration of gabapentin with oral contraceptives including norethindron, norethisterone and/or ethinyl estradiol does not influence the steady-state pharmacokinetics of either component.