Lansoprazole

No reports of enterochromaffin-like (ECL) cell carcinoids, dysplasia, or neoplasia has occurred.

Use of proton pump inhibitors (PPIs) may increase risk of CDAD, especially in hospitalized patients; consider CDAD diagnosis in patients with persistent diarrhea that does not improve. Use the lowest dose and shortest duration of PPI therapy appropriate for the condition being treated.

Has been reported as new onset or exacerbation of existing autoimmune disease; most cases were cutaneous lupus erythematosus (CLE), most commonly, subacute CLE (occurring within weeks to years after continuous therapy). Systemic lupus erythematosus (SLE) is less common (typically occurs within days to years after initiating treatment) and occurred primarily in young adults up to elderly patients. Discontinue therapy if signs or symptoms of CLE or SLE occur and refer to a specialist for evaluation; most patients improve 4 to 12 weeks after discontinuation of lansoprazole.

Increased incidence of osteoporosis-related bone fractures of the hip, spine, or wrist may occur with proton pump inhibitor (PPI) therapy. Patients on high-dose or long-term therapy should be monitored. Use the lowest effective dose for the shortest duration of time, use vitamin D and calcium supplementation, and follow appropriate guidelines to reduce risk of fractures in patients at risk.

Reported rarely, usually with prolonged PPI use of ≥3 months (most cases >1 year of therapy). May be symptomatic or asymptomatic; severe cases may cause tetany, seizures, and cardiac arrhythmias. Consider obtaining serum magnesium concentrations prior to beginning long-term therapy, especially if taking concomitant digoxin, diuretics, or other drugs known to cause hypomagnesemia; and periodically thereafter. Hypomagnesemia may be corrected by magnesium supplementation, although discontinuation of lansoprazole may be necessary; magnesium levels typically return to normal within 1 week of stopping.

Acute interstitial nephritis has been observed in patients taking PPIs; may occur at any time during therapy and is generally due to an idiopathic hypersensitivity reaction. Discontinue if acute interstitial nephritis develops.

Prolonged treatment (≥2 years) may lead to vitamin B12 malabsorption and subsequent vitamin B12 deficiency. The magnitude of the deficiency is dose-related and the association is stronger in females and those younger in age ( Disease-related concerns:

Relief of symptoms does not preclude the presence of a gastric malignancy.

Use of PPIs may increase risk of these infections.

Patients with severe liver dysfunction may require dosage reductions. Concurrent drug therapy issues:

Proton pump inhibitors (PPIs) may diminish the therapeutic effect of clopidogrel thought to be due to reduced formation of the active metabolite of clopidogrel. The manufacturer of clopidogrel recommends either avoidance of both omeprazole (even when scheduled 12 hours apart) and esomeprazole or use of a PPI with comparatively less effect on the active metabolite of clopidogrel (eg, pantoprazole). Although lansoprazole exhibits the most potent CYP2C19 inhibition in vitro (Li 2004; Ogilvie 2011), an in vivo study of extensive CYP2C19 metabolizers showed less reduction of the active metabolite of clopidogrel by lansoprazole/dexlansoprazole compared to esomeprazole/omeprazole (Frelinger 2012). The manufacturer of lansoprazole states that no dosage adjustment is necessary for clopidogrel when used concurrently. In contrast to these warnings, others have recommended the continued use of PPIs, regardless of the degree of inhibition, in patients with a history of GI bleeding or multiple risk factors for GI bleeding who are also receiving clopidogrel since no evidence has established clinically meaningful differences in outcome; however, a clinically significant interaction cannot be excluded in those who are poor metabolizers of clopidogrel (Abraham 2010; Levine 2011).

Potentially significant interactions may exist, requiring dose or frequency adjustment, additional monitoring, and/or selection of alternative therapy. Consult drug interactions database for more detailed information. Dosage form specific issues:

Some dosage forms may contain benzyl alcohol; large amounts of benzyl alcohol (≥99 mg/kg/day) have been associated with a potentially fatal toxicity (“gasping syndrome”) in neonates; the “gasping syndrome” consists of metabolic acidosis, respiratory distress, gasping respirations, CNS dysfunction (including convulsions, intracranial hemorrhage), hypotension, and cardiovascular collapse (AAP ["Inactive" 1997]; CDC 1982); some data suggests that benzoate displaces bilirubin from protein binding sites (Ahlfors 2001); avoid or use dosage forms containing benzyl alcohol with caution in neonates. See manufacturer's labeling.

Some products may contain phenylalanine, which can be harmful to patients with phenylketonuria (PKU). Before prescribing, consider the combined daily amount of phenylalanine from all sources. Other warnings/precautions:

Helicobacter pylori eradication: Short-term combination therapy (≤7 days) has been associated with a higher incidence of treatment failure. The American College of Gastroenterology recommends 10 to 14 days of therapy (triple or quadruple) for eradication of H. pylori (Chey 2017).

Serum chromogranin A (CgA) levels increase secondary to drug-induced decreases in gastric acid; may cause false-positive results in diagnostic investigations for neuroendocrine tumors. Temporarily stop lansoprazole treatment at least 14 days before CgA test; if CgA level is high, repeat test to confirm. Use same commercial laboratory for testing to prevent variable results.

When used for self-medication, patients should be instructed not to use if they have difficulty swallowing, are vomiting blood, or have bloody or black stools. Prior to use, patients should contact healthcare provider if they have liver disease, heartburn for >3 months, heartburn with dizziness, lightheadedness, or sweating, MI symptoms, frequent chest pain, frequent wheezing (especially with heartburn), unexplained weight loss, nausea/vomiting, stomach pain, or are taking antifungals, atazanavir, digoxin, tacrolimus, theophylline, or warfarin. Patients should stop use and consult a healthcare provider if heartburn continues or worsens, or if they need to take for >14 days or more often than every 4 months. Patients should be informed that it may take 1 to 4 days for full effect to be seen.