Drug reference

Lansoprazole

Proton Pump Inhibitor · Antiulcer agent

Proton Pump InhibitorAntiulcer agent

CDSCO approved

EXCRETION

—

not curated

INTERACTIONS

12 major

incl. contraindicated

PREGNANCY

Manufacturer advises avoid.

FDA category + note

Top interactionssee all 12 →

RilpivirineContraindicatedDatabaseDDInter
AcalabrutinibSevereDatabaseDDInter
AtazanavirSevereDatabaseDDInter
CilostazolSevereDatabaseDDInter

Mechanism

Lansoprazole is a substituted benzimidazole prodrug that accumulates in the acidic canaliculi of gastric parietal cells, where it undergoes acid-catalyzed conversion to the active sulfenamide form. This reactive intermediate binds covalently to cysteine residues on the alpha subunit of H+/K+-ATPase (the proton pump), irreversibly inhibiting acid secretion. Because new pump molecules must be synthesized to restore acid output, a single daily dose suppresses gastric acid secretion by 80-95% for 24 hours.

Indications

Helicobacter pylori eradication (in combination with other drugs)Benign gastric ulcerDuodenal ulcerNSAID-associated duodenal ulcerNSAID-associated gastric ulcerProphylaxis of NSAID-associated duodenal ulcerProphylaxis of NSAID-associated gastric ulcerZollinger–Ellison syndrome (and other hypersecretory conditions)Gastro-oesophageal reflux diseaseSevere oesophagitisSevere oesophagitis, refractory to initial treatment (off-label)Functional dyspepsia (off-label)Uninvestigated dyspepsia (off-label)Gastric ulcersDuodenal ulcersErosive esophagitisGastroesophageal reflux diseaseHelicobacter pylori eradicationZollinger-Ellison syndromePathological hypersecretory conditionsReducing the risk of duodenal ulcer recurrence associated with H. pylori infectionsSelf-treatment of acid reflux (over-the-counter)Treatment and prevention of recurrence of NSAID-associated gastric ulcersPeptic ulcerGastroesophageal reflux disease (GERD)H. pylori eradication therapy

Dosing

Adult: Helicobacter pylori eradication: 30 mg twice daily for 7 days (first- and second-line eradication therapy); 10 days (third-line eradication therapy). Benign gastric ulcer: 30 mg once daily for 8 weeks, dose to be taken in the morning. Duodenal ulcer: 30 mg once daily for 4 weeks, dose to be taken in the morning; maintenance 15 mg once daily.…
Pediatric: Children 1–11 years: max. 10 mg daily in severe impairment. Children 12–17 years: max. 20 mg daily in severe impairment.
Renal adjustment: Manufacturer advises caution in severe renal insufficiency.
Hepatic adjustment: 50% dose reduction in moderate to severe impairment.
Max dose: Children 1–11 years: max. 10 mg daily in severe impairment. Children 12–17 years: max. 20 mg daily in severe impairment. For Zollinger–Ellison syndrome, daily doses of 120 mg or more are given in two divided doses.

Pharmacokinetics

Onset

Faster onset of action

Half-life

0.5 to 3 h (parent compound)

Bioavailability

Higher oral bioavailability

Protein binding

Highly protein bound.

Metabolism

Extensively metabolized by hepatic CYPs, particularly CYP2C19 and CYP3A4.

Contraindications

Pregnancy
Breastfeeding

Side effects

Common

Dry throatFatigueHeadacheNauseaAbdominal painConstipationFlatulenceDiarrheaLoose stoolsMuscle and joint painDizziness

Serious

Eosinophilia
Oedema
Anaemia
Angioedema
Appetite decreased
Erectile dysfunction
Fever
Glossitis
Oesophageal candidiasis
Pancreatitis
Restlessness
Tremor
Subacute myopathy
Arthralgias
Interstitial nephritis
Pharyngitis
Skin rashes
Increased risk of bone fracture
Increased susceptibility to hospital-acquired pneumonia
Increased susceptibility to community-acquired Clostridium difficile infection
Increased susceptibility to spontaneous bacterial peritonitis (in patients with ascites)
Hypomagnesemia
Vitamin B12 (cobalamin) deficiency (with long-term use, >3 years)
Hypergastrinemia leading to ECL hyperplasia and fundic gland polyposis
Atrophic gastritis
Rashes (1.5% incidence)
Leucopenia (infrequent)
Hepatic dysfunction (infrequent)
Atrophic gastritis (occasionally on prolonged treatment)
Gynaecomastia (on prolonged use)
Erectile dysfunction (on prolonged use)
Accelerated osteoporosis (among elderly patients with high-dose long-term use for GERD)

Pregnancy & lactation

Pregnancy

Manufacturer advises avoid.

Lactation

Avoid—present in milk in animal studies.

Drug interactions

Rilpivirine

Contraindicated

Database

Reduced absorption and plasma concentrations of rilpivirine, potentially leading to loss of efficacy.

Should not be given with proton pump inhibitors.

Source: DDInter

Acalabrutinib

Severe

Database

Drug interaction classified as: absorption

Source: DDInter

Atazanavir

Severe

Database

Substantially reduced atazanavir concentrations, leading to loss of antiviral effectiveness.

Proton pump inhibitors should be avoided in patients receiving atazanavir without ritonavir.

Source: DDInter

Cilostazol

Severe

Database

Drug interaction classified as: metabolism.

Source: DDInter

Citalopram

Severe

Database

Drug interaction classified as: metabolism.

Source: DDInter

Dacomitinib

Severe

Database

Clinical effect not specified

Source: DDInter

Dasatinib

Severe

Database

Reduced plasma concentrations of dasatinib, potentially leading to decreased efficacy in treating chronic myeloid leukemia (CML) or acute lymphoblastic leukemia (ALL).

Avoid concomitant use. If an acid-suppressing agent is required, consider alternative agents (e.g., H2-receptor antagonists with careful timing, or antacids with strict separation). If lansoprazole is essential, monitor for signs of reduced dasatinib efficacy and consider dose adjustments, though this may not fully overcome the interaction.

Source: DDInter

Erlotinib

Severe

Database

Reduced plasma levels and potentially reduced efficacy of erlotinib.

Avoid concomitant use. If an acid-suppressing agent is required, consider alternative agents (e.g., H2-receptor antagonists with careful timing, or antacids with strict separation). If lansoprazole is essential, monitor for signs of reduced erlotinib efficacy and consider dose adjustments, though this may not fully overcome the interaction.

Source: DDInter

Methotrexate

Severe

Database

Increased methotrexate levels, potentially leading to toxicity.

Not specified, but typical management involves monitoring methotrexate levels.

Source: DDInter

Nelfinavir

Severe

Database

Significantly reduced plasma concentrations of nelfinavir, leading to decreased antiviral efficacy and potential development of HIV resistance.

Concomitant use is generally not recommended. If an acid-suppressing agent is required, consider alternative antiretrovirals or alternative acid-suppressing agents (e.g., H2-receptor antagonists with careful timing, or antacids with strict separation). If lansoprazole is essential, nelfinavir dose adjustment and close monitoring of viral load may be necessary, but this is often insufficient.

Source: DDInter

Neratinib

Severe

Database

Clinical effect not specified

Source: DDInter

Pazopanib

Severe

Database

Source: DDInter