Aciphex contains rabeprazole - a proton pump inhibitor which suppresses gastric acid secretion in the stomach. Rabeprazole restricts the gastric H+, K+ATPase at the secretory surface of the gastric parietal cell. That is why the medication is suggested to have properties of gastric proton-pump inhibitors. Aciphex stops the final stage of gastric acid discharge and thus stops the symptoms of gastroesophageal reflux disease. Rabeprazole is modified in gastric parietal cells to an active sulfenamide. The medication works very quickly and effectively helps patients with heartburn caused by GERD. It is chemically activated at pH 1.2 with half-life of 78 seconds. It prevents acid carriage with a half-life of 90 seconds.