There is a slight interaction between Zegerid (Omeprazole/Sodium Bicarb) and gabapentin. Antacids (e.g., aluminum hydroxide; magnesium hydroxide) have been shown to reduce the oral bioavailability of gabapentin by roughly 20%.  Even though Zegerid doesn't specifically contain large amounts of aluminum or magnesium, it is still recommended to separate it from gabapentin. The decrease in bioavailability was about 5% when gabapentin was administered 2 hours after the antacid. It is recommended that gabapentin be taken at least 2 hours following the administration of antacids in order to avoid a significant interaction.