Aciphex

Rabeprazole, sold under the brand name Aciphex among others, is a proton pump inhibitor that decreases stomach acid production. It is used to treat peptic ulcer disease, gastroesophageal reflux disease, and conditions of excess stomach acid production such as Zollinger-Ellison syndrome, and it is used in combination with other medicines to help eradicate Helicobacter pylori infection. It works by blocking the H+/K+-ATPase enzyme in the acid-producing parietal cells of the stomach lining, permanently binding cysteine residues on the enzyme to form disulfide bonds that stop acid secretion. Rabeprazole was patented in 1986 and gained medical approval in 1997, reaching the United States market after FDA approval in 1999; it is now available as a generic medication and was the 288th most frequently prescribed medication in the United States in 2017. Its effectiveness is considered comparable to other proton pump inhibitors. Common side effects include constipation, weakness and throat inflammation, while more serious risks with long-term use include osteoporosis, low blood magnesium, Clostridioides difficile infection and pneumonia.