Information about Lansoprazole
Lansoprazole is a proton pump inhibitor (PPI) and a potent inhibitor of gastric acidity which is widely used in the therapy of gastroesophageal reflux and peptic ulcer disease. Dexlansoprazole is an isomer of lansoprazole that has a similar spectrum of activity and toxicities.
Liver safety of Lansoprazole
Lansoprazole therapy is associated with a low rate of transient and asymptomatic serum aminotransferase elevations and is a reported, but very rare cause of clinically apparent liver injury.
Mechanism of action of Lansoprazole
Lansoprazole (lan soe' pra zole), like other PPIs, binds to and inactivates the hydrogen/ potassium (H+/K+) ATPase of gastric parietal cells, causing inhibition of the proton pump that transports H+ into the gastric lumen, the final common step in gastric acid production. Lansoprazole is a prodrug and is converted to the active form in the acidic secretory canaliculi of parietal cells. Because the inhibition is irreversible, acid secretion is suppressed for 24 to 48 hours, until new proton pump molecules have been synthesized and transported to the cell membrane.
FDA approval information for Lansoprazole
Lansoprazole was the second PPI approved for use in the United States (1995) and dexlansoprazole, a stereoisomer, was approved for use in 2009. Lansoprazole is available in 15 and 30 mg delayed release capsules and tablets, as well as granules for oral suspension and in vials for parenteral use under the brand name of Prevacid. Over-the-counter formulations have also become available. The typical dose in adults with peptic ulcer disease is 15 mg daily for 4 to 8 weeks and similar dose chronically for maintenance therapy. Higher doses are recommended for more severe cases of gastrointestinal reflux and peptic ulcer disease, and doses of up to 120 mg daily for Zollinger-Ellison syndrome. Combinations of lansoprazole with antibiotics for 10 to 14 days are effective and recommended for eradication of H. pylori infection. Dexlansoprazole is available by prescription only in capsules of 30 or 60 mg under the brand name Dexilant.
Dosage and administration for Lansoprazole
The recommended dose of dexlansoprazole is 30 to 60 mg once daily. Both lansoprazole and dexlanscprazole are very well tolerated.
Side effects of Lansoprazole
Side effects are uncommon and usually mild: they can include diarrhea, nausea, vomiting, abdominal discomfort, flatulence, skin rash, headaches and dizziness. Severe adverse events are rare but can include hypersensitivity reactions. Long-term use may be associated with bone fractures, acute interstitial nephritis, lupus erythematosus, vitamin B12 deficiency and hypomagnesemia.
The antiulcer agents in clinical use