LANSOPRAZOLE
Clinical safety rating: safe
Animal studies have demonstrated safety
Proton pump inhibitor that inhibits gastric acid secretion by binding to the H+/K+ ATPase enzyme (proton pump) in gastric parietal cells, preventing the final step of acid production.
| Metabolism | Primarily metabolized by CYP2C19 and CYP3A4 to inactive metabolites; undergoes significant first-pass metabolism. |
| Excretion | Renal (14-23% as metabolites); biliary/fecal (major route, ~60% as metabolites and parent drug). |
| Half-life | Terminal elimination half-life: 1.5-2 hours (increased to 3-6 hours in elderly, hepatic impairment). |
| Protein binding | 97% bound to albumin. |
| Volume of Distribution | 0.3 L/kg (indicates distribution into total body water). |
| Bioavailability | Oral: 80-90% (first-pass metabolism minimal). |
| Onset of Action | Oral: 1-2 hours (single dose); IV: 30 minutes. |
| Duration of Action | Acid suppression persists >24 hours due to prolonged binding to proton pumps; dosing once daily. |
| Molecular Weight | 369.36 |
15-30 mg orally once daily; 30 mg IV over 30 minutes once daily (when oral not possible).
| Dosage form | CAPSULE, DELAYED REL PELLETS |
| Renal impairment | No dose adjustment required in renal impairment. Hemodialysis does not remove lansoprazole; no supplemental dose needed. |
| Liver impairment | Moderate to severe hepatic impairment (Child-Pugh B or C): reduce dose to 15 mg orally once daily. |
| Pediatric use | 1-11 years (≤30 kg): 15 mg orally once daily; >30 kg: 30 mg orally once daily. 12-17 years: 15-30 mg orally once daily. |
| Geriatric use | No specific dose adjustment, but consider lower starting dose (15 mg daily) due to decreased hepatic function and prolonged half-life in elderly. |
| 1st trimester | Limited human data; animal studies not suggestive of harm. Avoid unless clearly needed. |
| 2nd trimester | Limited human data; no known risk. May use if indicated. |
| 3rd trimester | Limited human data; no known risk. May use if indicated. |
Clinical note
Can reduce absorption of drugs requiring gastric pH for absorption (eg ketoconazole) May increase risk of Clostridium difficile-associated diarrhea and bone fractures with long-term use.
| Placental transfer | Crosses placenta in animals; human data limited but likely minimal transfer due to high protein binding and molecular weight. |
| Breastfeeding | Lansoprazole is excreted into breast milk in low concentrations; doses up to 30 mg daily are unlikely to cause adverse effects in breastfed infants. Monitor infant for potential gastrointestinal effects. |
■ FDA Black Box Warning
None.
| Common Effects | erosive esophagitis |
| Serious Effects |
History of hypersensitivity to lansoprazole or any component of the formulationConcomitant use with rilpivirine-containing products
| Precautions | Increased risk of Clostridium difficile-associated diarrhea, bone fracture (hip, wrist, spine) with long-term use, hypomagnesemia with prolonged treatment, vitamin B12 deficiency with chronic use, and acute interstitial nephritis., May mask symptoms of gastric malignancy., Interaction with clopidogrel: potential reduced antiplatelet effect (controversial). |
| Food/Dietary | Administration with food reduces bioavailability; take before meals (at least 30 minutes). Avoid concomitant intake of high-fat meals immediately before dosing as they may delay absorption. Lansoprazole can be taken with antacids, but separate by at least 1 hour. There are no specific dietary restrictions, but acidic foods (citrus, tomatoes) and caffeine may exacerbate symptoms. Reduced gastric acidity may affect absorption of drugs requiring acidic pH (e.g., atazanavir, nelfinavir, iron supplements, erlotinib). |
Loading safety data…
| Lactation Rating |
| L2 (probably compatible) |
| Teratogenic Risk | In the first trimester, limited data suggest no major increase in congenital malformations (minor risk or none). Second and third trimesters: no specific fetal toxicity reported; however, consider potential for hypocalcemia and reduced vitamin B12 absorption with prolonged use. |
| Fetal Monitoring | Maternal monitoring: For long-term use, monitor magnesium levels, vitamin B12 levels, and bone density. Fetal monitoring: Routine obstetric ultrasound; no specific additional monitoring required. |
| Fertility Effects | No known adverse effects on fertility in humans. In animal studies, no impairment of fertility observed. |
| Clinical Pearls | Lansoprazole is a prodrug activated in acidic parietal cell canaliculi; administer before meals (preferably breakfast) for maximal acid suppression. Onset of symptom relief occurs within 1-3 days but full healing may take 4-8 weeks. Do not crush or chew delayed-release capsules; may open and sprinkle on soft food (applesauce) for patients with dysphagia. Long-term use (≥1 year) increases risk of Clostridioides difficile infection, osteoporosis-related fractures, and vitamin B12 deficiency. Consider de-escalation to on-demand or step-down therapy in appropriate patients. Monitor for hypomagnesemia if used with diuretics or digoxin. For IV therapy, reconstitute with sterile water and administer over 30 minutes; do not mix with other medications. |
| Patient Advice | Take lansoprazole exactly as prescribed, preferably 30-60 minutes before a meal (typically breakfast). · Swallow capsules whole; do not crush or chew. If you have difficulty swallowing, you may open the capsule and sprinkle the contents on a tablespoon of applesauce, yogurt, or pudding. Swallow immediately without chewing. · Do not take with other acid reducers (antacids, H2 blockers) without consulting your doctor. · Avoid drinking alcohol, as it can increase stomach acid and worsen symptoms. · Tell your doctor if you experience severe diarrhea, joint pain, rash, or signs of low magnesium (muscle cramps, irregular heartbeat, seizures). · Long-term use may increase risk of bone fractures; ensure adequate calcium and vitamin D intake. · Do not stop taking lansoprazole abruptly; consult your doctor for a tapering plan if needed. |