Brands, Medical Use, Clinical Data
- Anti-ulcer Agents
- Proton-pump Inhibitors
Brands / Synonyms
Agopton; Amarin; Aprazol; Bamalite; Biuret; Biuret Gr; Biuret Reagent; Biuret Reagent Solution; Blason; Compraz; Dakar; Ilsatec; Ketian; Lancid; Lanproton; Lansopep; Lansoprazol [Inn-Spanish]; Lansoprazole [Usan:Ban:Inn]; Lansoprazolum [Inn-Latin]; Lanston; Lanz; Lanzol-30; Lanzopral; Lanzor; Lasoprol; Limpidex; Mesactol; Monolitum; Ogast; Ogastro; Opiren; Prevacid; Prevacid I.V.; Prevacid Iv; Prevacid Naprapac; Prevacid Solutab; Prevpac; Prezal; Pro Ulco; Promp; Prosogan; Suprecid; Takepron; Ulpax; Zoprol; Zoton
For treatment of Acid-reflux disorders (GERD), peptic Ulcer Disease, duodenal ulcers, esophagitis, and Zollinger-Ellison syndrome
Lansoprazole, an acid proton-pump inhibitor similar to omeprazole, is used as an untiulcer drug in the treatment and maintenance of healing of duodenal or gastric ulcers, erosive and reflux esophagitis, NSAID-induced ulcer, Zollinger-Ellison syndrome, and Barrett's esophagus. Lansoprozole is active against Helicobacter pylori. The plasma elimination half-life of lansoprazole does not reflect its duration of suppression of gastric acid secretion. Thus, the plasma elimination half-life is less than two hours, while the acid inhibitory effect lasts more than 24 hours.
Mechanism of Action
Lansoprazole belongs to a class of antisecretory compounds, the substituted benzimidazoles, that do not exhibit anticholinergic or histamine H2-receptor antagonist properties, but rather suppress gastric acid secretion by specific inhibition of the (H+,K+)-ATPase enzyme system at the secretory surface of the gastric parietal cell. Because this enzyme system is regarded as the acid (proton) pump within the parietal cell, Lansoprazole has been characterized as a gastric acid-pump inhibitor, in that it blocks the final step of acid production. This effect is dose-related and leads to inhibition of both basal and stimulated gastric acid secretion irrespective of the stimulus.
The absorption of lansoprazole is rapid, with mean Cmax occurring approximately 1.7 hours after oral dosing, and relatively complete with absolute bioavailability over 80%.
Symptoms of overdose include abdominal pain, nausea and diarrhea.
Biotrnasformation / Drug Metabolism
Hepatic. Two metabolites have been identified in measurable quantities in plasma (the hydroxylated sulfinyl and sulfone derivatives of lansoprazole). These metabolites have very little or no antisecretory activity. Lansoprazole is thought to be transformed into two active species which inhibit acid secretion by (H+,K+)-ATPase within the parietal cell canaliculus, but are not present in the systemic circulation.
Lansoprazole is contraindicated in patients with known hypersensitivity to any component of the formulation.
Lansoprazole delayed-release capsules are contraindicated in patients with known hypersensitivity to any component
of the formulation.
Amoxicillin is contraindicated in patients with a known hypersensitivity to any penicillin. (Please refer to full
prescribing information for amoxicillin before prescribing.)
Clarithromycin is contraindicated in patients with a known hypersensitivity to any macrolide antibiotic, and in
patients receiving terfenadine therapy who have preexisting cardiac abnormalities or electrolyte disturbances.
(Please refer to clarithromycin before prescribing.)
Lansoprazole is metabolized through the cytochrome P450 system, specifically through the CYP3A and
CYP2C19 isozymes. Studies have shown that lansoprazole does not have clinically significant interactions with other
drugs metabolized by the cytochrome P450 system, such as warfarin, antipyrine, indomethacin, ibuprofen,
phenytoin, propranolol, prednisone, diazepam, clarithromycin, or terfenadine in healthy subjects. These compounds are
metabolized through various cytochrome P450 isozymes including CYP1A2, CYP2C9, CYP2C19, CYP2D6, and CYP3A.
When lansoprazole was administered concomitantly with theophylline (CYP1A2, CYP3A), a minor increase (10%) in the
clearance of theophylline was seen. Because the small magnitude and the direction of the effect on theophylline
clearance, this interaction is unlikely to be clinical concern. Nonetheless, individual patients may require
additional titration of their theophylline dosage when lansoprazole is started or stopped to ensure clinically
effective blood levels.
Lansoprazole has also been shown to have no clinically significant interaction with amoxicillin.
In a single-dose crossover study examining lansoprazole 30 mg and omeprazole 20 mg each administered alone and
concomitantly with sucralfate 1 gram, absorption of the proton pump inhibitors was delayed and their bioavailability
was reduced by 17% and 16%, respectively, when administered concomitantly with sucralfate. Therefore, proton pump
inhibitors should be taken at least 30 minutes prior to sucralfate. In clinical trials, antacids were administered
concomitantly with lansoprazole delayed-release capsules; this did not interfere with its effect.
Lansoprazole causes a profound and long lasting inhibition of gastric acid secretion; therefore, it is
theoretically possible that lansoprazole may interfere with the absorption of drugs where gastric pH is an important
determinant of bioavailability (e.g. ketoconazole, ampicillin esters, iron salts, digoxin).