Lansoprazole (/lænˈsoʊprəzoʊl/ lan-SOH-prə-zohl; INN) is a proton-pump inhibitor (PPI) which inhibits the stomach's production of gastric acids. It is manufactured by a number of companies worldwide under several brand names. In the United States, it was first approved by the Food and Drug Administration (FDA) in 1995.[1] Prevacid patent protection expired on November 10, 2009.[2][3] Since 2009, lansoprazole has been available over the counter (OTC) in the U.S. in a 15-mg dose marketed by Novartis as Prevacid 24HR.[4][5][6] In Australia, it is marketed by Pfizer as Zoton.

Starting at
| (RS)-2-([3-methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsulfinyl)-1H-benzo[d]imidazole |
| Trade names | Prevacid |
| AHFS/Drugs.com | monograph |
| MedlinePlus | a695020 |
| Licence data | US FDA:link |
| Pregnancy category |
AU: B3
US: B (No risk in non-human studies) |
| Legal status |
UK: POM (Prescription only) US: OTC |
| Routes of administration |
Oral, IV |
| Bioavailability | 80% or more |
| Protein binding | 97% |
| Metabolism | Hepatic (CYP3A4- and CYP2C19-mediated) |
| Biological half-life | 1–1.5 hours |
| Excretion | Renal and fecal |
| CAS Number | 103577-45-3 |
| ATC code | A02BC03 |
| PubChem | CID: 3883 |
| IUPHAR/BPS | 7208 |
| DrugBank | DB00448 |
| ChemSpider | 3746 |
| UNII | 0K5C5T2QPG |
| KEGG | D00355 |
| ChEBI | CHEBI:6375 |
| ChEMBL | CHEMBL480 |