Lanproton - General Information
Lanproton is a proton pump inhibitor which prevents the stomach from producing acid. It is manufactured by TAP Pharmaceutical Products. Lanproton has been marketed for many years and is one of several PPI's available.
Pharmacology of Lanproton
Lanproton, 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.
Lanproton for patients
Lansoprazole is used short-term (4-8 weeks) to treat duodenal ulcer and erosive esophagitis. It may used long term to treat Zollinger-Ellison syndrome, a problem with too much acid being secreted. Lansoprazole capsules should be taken before eating. The capsules are delayed release' meaning they work over time. The capsules should be swallowed whole and not crushed, opened or chewed. If you are taking theophylline, you may need your dosage checked when you start and stop lansoprazole to ensure your dose is effective. If you are taking sucralfate, it should be taken 30 minutes after taking lansoprazole. The most common side effects reported were diarrhea, nausea and abdominal pain. These occurred in fewer than 5% of patients. If your symptoms return after completing your course of therapy, talk to your physician for further evaluation.
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).
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.)
Additional information about Lanproton
Lanproton Indication: For treatment of Acid-reflux disorders (GERD), peptic Ulcer Disease, duodenal ulcers, esophagitis, and Zollinger-Ellison syndrome
Mechanism Of Action: Lanproton 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, Lanproton 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.
Drug Interactions: Atazanavir This gastric pH modifier decreases the levels/effects of atazanavir
Enoxacin The agent decreases the absorption of enoxacin
Indinavir Omeprazole decreases the absorption of indinavir
Itraconazole The proton pump inhibitor decreases the absorption of imidazole
Ketoconazole The proton pump inhibitor decreases the absorption of imidazole
Sucralfate Sucralfate decreases the effect of lansoprazole
Food Interactions: Avoid alcohol.
Take 30-60 minutes before meals.
Food reduces bioavailabilty, but this has very little clinical impact.
Generic Name: Lansoprazole
Synonyms: Not Available
Drug Category: Anti-Ulcer Agents; Anti-Infectives; Proton-pump Inhibitors
Drug Type: Small Molecule; Approved
Absorption: 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%.
Toxicity (Overdose): Symptoms of overdose include abdominal pain, nausea and diarrhea.
Protein Binding: 97%
Biotransformation: 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.
Half Life: 1.5 (± 1.0) hours
Dosage Forms of Lanproton: Tablet, delayed release Oral
Capsule, delayed release Oral
Chemical IUPAC Name: 2-[[3-methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsulfinyl]-1H-benzimidazole
Chemical Formula: C16H14F3N3O2S
Lansoprazole on Wikipedia: https://en.wikipedia.org/wiki/Lansoprazole
Organisms Affected: Humans and other mammals