Lansoprazole

What it is

Lansoprazole is a prescription and over-the-counter medicine, one of the substituted benzimidazoles, that shuts down the acid pump of the stomach's parietal cells. It is swallowed as a delayed-release capsule or an orally disintegrating tablet in 15 mg and 30 mg strengths, and a 15 mg non-prescription version is sold for frequent heartburn. The US label records it as a proton pump inhibitor approved for duodenal and gastric ulcer, H. pylori eradication regimens, NSAID-associated gastric ulcer, symptomatic gastro-oesophageal reflux disease, erosive oesophagitis and pathological hypersecretory conditions. Its first US approval was in 1995.

What the research says

Lansoprazole reliably cuts stomach acid, and the randomised evidence for healing damaged oesophagus and preventing ulcers is strong and quantified: 8-week healing rate ratio 1.62 (95% CI 1.46-1.76) against ranitidine, and 67% versus 13% still healed at a year on maintenance. The evidence is weaker for the things it is most often taken for long-term. For functional dyspepsia, an off-label use, Cochrane found a small benefit over placebo with a number needed to treat of 11 and no clear advantage over H2-blockers. On harms, the largest randomised test of three years of a PPI found no excess of pneumonia, fracture, kidney disease, dementia, cancer or death, and only a small excess of enteric infection, which contradicts much of the observational alarm; but observational studies do link long use to vitamin B12 and iron deficiency, and the label carries warnings about magnesium, fracture, C. difficile and interstitial nephritis. Stopping has its own problem: a randomised trial in healthy volunteers found acid symptoms appearing after an eight-week course ended, in 44% versus 15% on placebo.

Evidence grade: Well established.

How it works

Drug class: Proton pump inhibitor (substituted benzimidazole gastric acid pump inhibitor)

Lansoprazole is taken up by the acid-producing cells of the stomach lining and permanently blocks the enzyme pump that moves acid into the stomach, so far less acid is produced whatever is stimulating it. Because the block is at the last step, it works regardless of whether the signal to make acid came from food, histamine or nerves. (Source 1)

What it is used for

• Randomised trials and a meta-analysis show lansoprazole heals erosive oesophagitis more often than ranitidine at 8 weeks and about as often as omeprazole, and 15 mg daily keeps far more people healed at a year than ranitidine (67% versus 13%). Evidence: established. (Source 2)
• The FDA label lists these among the approved indications, with 15 mg or 30 mg once daily and a 30 mg twice-daily dose inside triple therapy. We did not retrieve independent outcome trials for these specific indications in this run, so the strength of the evidence here rests on the label as a regulatory position plus the class-wide healing data. Evidence: established. (Source 3)
• In a 537-patient randomised trial in H. pylori-negative long-term NSAID users, 80-82% on lansoprazole were ulcer-free at 12 weeks against 51% on placebo, but 93% on full-dose misoprostol did better still. Evidence: established. (Source 4)
• Approved for adults and children aged 1 year and over; the meta-analysed trials show PPIs beat both ranitidine and placebo for heartburn resolution and relapse, with lansoprazole no different from omeprazole. Evidence: established. (Source 2)
• Cochrane found PPIs modestly better than placebo (RR 0.88, 95% CI 0.82 to 0.94, NNTB 11, moderate quality) but with little or no advantage over H2-receptor antagonists. The effect is small and the drugs are not approved for this. Evidence: limited. (Source 5)
• Cochrane's deprescribing review found on-demand instead of continuous dosing cut pill burden but increased symptom breakthrough, and had too little data to judge long-term benefits and harms either way. Evidence: disputed. (Source 6)

Interactions

• Iron salts (and other supplements or drugs that need stomach acid to dissolve) (label): Lansoprazole raises the pH inside the stomach, and anything that needs acid to dissolve is absorbed less well. The label names iron salts explicitly. (Source 7)
• Iron (clinical consequence: iron-deficiency anaemia) (case reports): Beyond the absorption mechanism, a national claims case-control study found long-term PPI or H2-blocker use associated with more than double the odds of iron-deficiency anaemia. This is an association in routine care, not a controlled trial. (Source 8)
• Vitamin B12 (cyanocobalamin) (case reports): Suppressing acid for years can impair the release of vitamin B12 from food, and the label says daily use beyond about three years may lead to malabsorption or deficiency. A case-control study of over 25,000 people with new B12 deficiency found a 65% higher odds with two or more years' supply of PPIs. (Source 9)
• Magnesium and calcium (label): PPIs have rarely caused low blood magnesium after three months or more of use, which can in turn lower calcium and potassium. The label suggests considering magnesium and calcium measurement before starting and periodically in people already at risk of low calcium, and says magnesium or calcium supplementation may be needed. (Source 10)
• Warfarin (label): INR and prothrombin time have risen in people taking a PPI with warfarin, which can cause abnormal bleeding. (Source 11)
• Food (taking the capsule after a meal rather than before) (pharmacokinetic study): Food substantially cuts how much lansoprazole gets into the blood. Peak level and total exposure fall by roughly half to two thirds if it is taken 30 minutes after eating instead of fasting, and there is no meaningful food effect if it is taken before a meal. (Source 12)
• Alcohol (label): We found no documented pharmacokinetic or clinical interaction between lansoprazole and alcohol in the sources we read. The label states that Tables 2 and 3 are where it records drugs with clinically important interactions, and alcohol appears nowhere in the label; the word does not occur in it at all. We found no trial or case series of the combination either. Alcohol is an independent irritant of the stomach and oesophagus, but that is not an interaction with the drug. (Source 13)
• Methotrexate (label): Taking a PPI with methotrexate, mainly at high dose, can raise and prolong methotrexate levels and cause toxicity; the label says a temporary withdrawal of lansoprazole may be considered. (Source 14)

Stopping it

• Stopping a PPI after an eight-week course can itself produce heartburn, regurgitation or dyspepsia in people who never had them. In a double-blind randomised trial the drug was esomeprazole 40 mg a day, not lansoprazole: 44% of healthy volunteers who had taken it reported at least one relevant acid symptom in the four weeks after stopping, against 15% on placebo (P < .001). The authors read this as support for rebound acid hypersecretion having clinical consequences, and as a route into unintended dependence on the drug. Applying it to lansoprazole is a class extrapolation. (Source 15)
• The acid-output evidence behind rebound is much weaker than the symptom evidence. A systematic review of eight studies, five of them finding nothing, concluded that the studies are heterogeneous and that there is no strong evidence of a clinically relevant rise in acid production after stopping, with any signal limited to H. pylori-negative people after eight weeks of treatment. (Source 16)
• Cochrane's review of deprescribing in long-term users found that on-demand rather than continuous dosing reduced pill burden by about 3.79 pills a week (95% CI -4.73 to -2.84, moderate quality), but raised the risk of losing symptom control (RR 1.71, 95% CI 1.31 to 2.21, low quality) and reduced patient satisfaction. The review covered only people with mild reflux disease, and no trial reported a positive drug withdrawal effect. (Source 6)
• The non-prescription label sets its own stopping rule: people are told to stop and ask a doctor if heartburn continues or worsens, if they need the product for more than 14 days, if they need more than one course every four months, if they get diarrhoea, or if they develop a rash or joint pain. (Source 17)

What goes wrong

In short-term placebo-controlled trials of lansoprazole, diarrhoea, abdominal pain and constipation were reported slightly more often than on placebo, nausea at much the same rate, and diarrhoea stood out only at the 60 mg dose. (Source 18)

• Official position, Low certainty.
• Size: 2,768 lansoprazole-treated versus 1,023 placebo-treated patients.
• Who: participants in short-term, placebo-controlled lansoprazole studies.
• How long: short-term trials; durations not stated in the table.
• Result: Diarrhoea 3.8% versus 2.3% on placebo; abdominal pain 2.1% versus 1.2%; constipation 1.0% versus 0.4%; nausea 1.3% versus 1.2%, effectively identical. Across doses the label reports diarrhoea as similar to placebo at 15 mg and 30 mg and higher only at 60 mg: 2.9% placebo, 1.4% at 15 mg, 4.2% at 30 mg, 7.4% at 60 mg. There is therefore no dose-response across the usual approved adult range, and 15 mg was below placebo.
• Funding: manufacturer's label (Takeda), a regulatory position dated 2025-07-08, not an independent analysis.

Limit of this finding: There is no dose-response for diarrhoea across the usual approved adult doses: the label records 1.4% at 15 mg, which is LOWER than the 2.9% on placebo, and 4.2% at 30 mg. Only the 60 mg dose, which is above the usual approved adult dose, stands out at 7.4%. Nausea was 1.3% against 1.2% on placebo, which is the same rate, so it should not be read as an excess.

The incidence of diarrhea was similar between patients who received placebo and patients who received 15 and 30 mg of PREVACID, but higher in the patients who received 60 mg of PREVACID (2.9, 1.4, 4.2, and 7.4%, respectively).

The FDA-approved label records that long-term or multiple-daily-dose PPI therapy has been linked in observational studies to osteoporosis-related fracture of the hip, wrist or spine. (Source 19)

• Official position, Low certainty.
• Size: not stated; the label refers to several published observational studies.
• Who: PPI users in observational studies.
• How long: risk described as increased with therapy of a year or longer.
• Result: no effect size given in the label; it states only that risk was increased with high-dose and long-term therapy.
• Funding: manufacturer's label (Takeda), a regulatory position dated 2025-07-08.

Bone Fracture: Long-term and multiple daily dose PPI therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist or spine. (5.4)

In a large case-control study, two or more years' supply of PPIs was associated with a 65% higher odds of a vitamin B12 deficiency diagnosis, and the association rose with dose. (Source 20)

• Case-control study, Low certainty.
• Size: 25,956 cases with incident vitamin B12 deficiency and 184,199 controls.
• Who: Kaiser Permanente Northern California members, January 1997 to June 2011.
• How long: exposure defined as a 2 or more years' supply.
• Result: OR 1.65 (95% CI 1.58-1.73) for 2 or more years' supply of PPIs; OR 1.95 (95% CI 1.77-2.15) for more than 1.5 pills/day versus OR 1.63 (95% CI 1.48-1.78) for less than 0.75 pills/day (P = .007 for interaction)
• Funding: not stated in the abstract; the record lists Research Support, Non-U.S. Gov't. This is an observational association, not evidence of cause.

Both a 2 or more years' supply of PPIs (OR, 1.65 [95% CI, 1.58-1.73]) and a 2 or more years' supply of H2RAs (OR, 1.25 [95% CI, 1.17-1.34]) were associated with an increased risk for vitamin B12 deficiency. Doses more than 1.5 PPI pills/d were more strongly associated with vitamin B12 deficiency (OR, 1.95 [95% CI, 1.77-2.15]) than were doses less than 0.75 pills/d (OR, 1.63 [95% CI, 1.48-1.78]; P = .007 for interaction).

In a Taiwanese case-control study using national claims, long-term PPI or H2-blocker use was associated with more than double the odds of iron-deficiency anaemia. (Source 21)

• Case-control study, Low certainty.
• Size: 5,326 cases with iron-deficiency anaemia and 21,304 matched controls, drawn from 2 million longitudinal claims.
• Who: Taiwan National Health Insurance Research Database, 2011-2018.
• How long: exposure assessed over 1 year; long-term defined as 2 months or more.
• Result: adjusted OR 2.36 (95% CI 1.94-2.86, P < 0.001) overall; women aOR 2.16 (95% CI 1.73-2.70); the highest estimate, aOR 2.68 (95% CI 1.94-3.70), is attributed in the Results section to people aged 50 or over and in the paper's plain-language summary to women aged 50 or over.
• Funding: not stated. Observational; the study cannot separate the drug from the reason it was prescribed.

Limit of this finding: The paper is inconsistent about who the 2.68 figure belongs to: its Results section attributes it to people "aged >= 50 years", while its own plain-language summary attributes it to "females aged >= 50". Treat the over-50 estimate as uncertain in scope. The paper also prints "P < 0.05" beside an interval of 1.94-3.70, which on its own convention would be P < 0.001. Both oddities are the source's; the figures are quoted as printed.

Long-term (≥2 month) use of PPIs/H2 antagonists resulted in a higher risk of developing IDA than noncontinuous use/nonuse of those drugs (adjusted odds ratio [aOR] = 2.36, 95% confidence interval [CI] = 1.94-2.86

Hypomagnesaemia has been reported rarely after at least three months of PPI treatment and in most cases required magnesium replacement and stopping the drug. (Source 10)

• Official position, Low certainty.
• Size: not stated; the label describes case reports.
• Who: patients treated with PPIs for at least three months, in most cases after a year of therapy.
• How long: three months or more; usually after a year.
• Result: no rate given; serious events listed are tetany, arrhythmias and seizures.
• Funding: manufacturer's label (Takeda), a regulatory position dated 2025-07-08.

Hypomagnesemia, symptomatic and asymptomatic, has been reported rarely in patients treated with PPIs for at least three months, in most cases after a year of therapy. Serious adverse events include tetany, arrhythmias, and seizures.

Acute tubulointerstitial nephritis, a kidney inflammation, has been reported in people taking PPIs and can begin at any point in treatment. (Source 22)

• Case series, Very low certainty.
• Size: not stated; the label refers to reported case series.
• Who: patients taking PPIs.
• How long: may occur at any point during PPI therapy.
• Result: no rate is given; the label says some patients were diagnosed on biopsy and without extra-renal signs such as fever, rash or joint pain.
• Funding: manufacturer's label (Takeda), a regulatory position dated 2025-07-08.

Acute tubulointerstial nephritis (TIN) has been observed in patients taking PPIs and may occur at any point during PPI therapy.

In a randomised trial in healthy volunteers, 44% of those who had taken a proton pump inhibitor for eight weeks reported at least one new acid-related symptom in the four weeks after it was stopped, against 15% of those on placebo throughout. (Source 15)

• Randomized trial, Moderate certainty.
• Size: 120 healthy volunteers.
• Who: healthy volunteers with no acid-related diagnosis.
• How long: 12 weeks of placebo, or 8 weeks of esomeprazole 40 mg/d followed by 4 weeks of placebo.
• Result: 44% (26/59) of those randomized to PPI reported at least one relevant acid-related symptom in weeks 9-12 versus 15% (9/59) on placebo (P < .001), an absolute difference of about 29 percentage points.
• Funding: not stated; the record lists Research Support, Non-U.S. Gov't. The PPI used was esomeprazole, not lansoprazole, so this is class evidence.

Limit of this finding: The symptoms were self-reported on the Gastrointestinal Symptom Rating Scale, and the two groups did not differ on that scale at baseline, so the gap opened up during the withdrawal period rather than being there from the start.

Forty-four percent (26/59) of those randomized to PPI reported > or = 1 relevant, acid-related symptom in weeks 9-12 compared with 15% (9/59; P < .001) in the placebo group.

What the evidence supports

In a meta-analysis of randomised trials in erosive oesophagitis, lansoprazole 30 mg a day healed significantly more people at 8 weeks than ranitidine 300 mg a day (rate ratio 1.62, 95% CI 1.46-1.76), and no more than omeprazole 20 mg a day (1.02, 95% CI 0.98-1.06, an interval that includes 1 and so means equivalence). (Source 2)

• Meta-analysis, Moderate certainty.
• Size: 53 studies identified, of which 38 involved acute therapy and 15 maintenance therapy.
• Who: adults with endoscopically assessed erosive oesophagitis in randomised trials.
• How long: 8 weeks for healing; 1 year for relapse.
• Result: Versus ranitidine 300 mg/d the 8-week healing rate ratio for lansoprazole was 1.62 (95% CI, 1.46-1.76), a significant advantage. Versus omeprazole 20 mg/d it was 1.02 (95% CI, 0.98-1.06) - an interval that includes 1, so equivalence rather than superiority. The authors' own conclusion was that the newer PPIs were of similar efficacy to omeprazole and all PPIs superior to ranitidine and placebo.
• Funding: not stated in the abstract; the review was supported by research funding declared as Research Support, Non-U.S. Gov't.

Limit of this finding: Only the ranitidine comparison supports "more people healed". The omeprazole ratio of 1.02 with an interval from 0.98 to 1.06 means lansoprazole and omeprazole performed the same; it should not be read as lansoprazole being better.

The 8-week overall healing rate ratios in the comparison of newer PPIs with omeprazole 20 mg/d were as follows: lansoprazole 30 mg/d, 1.02 (95% CI, 0.98-1.06): rabeprazole 20 mg/d, 0.93 (95% CI, 0.87-1.00); and pantoprazole 40 mg/d, 0.98 (95% CI, 0.90-1.07). In the comparison of any PPI with ranitidine 300 mg/d, the ratios were as follows: lansoprazole, 1.62 (95% CI, 1.46-1.76); rabeprazole, 1.36 (95% CI, 1.20-1.54); pantoprazole, 1.60 (95% CI, 1.33-1.96); and omeprazole, 1.58 (95% CI, 1.41-1.78).

In maintenance of healed erosive oesophagitis, lansoprazole 15 mg daily kept 67% of people healed at one year against 13% on ranitidine, an absolute difference of about 54 percentage points. (Source 23)

• Randomized trial, Moderate certainty.
• Size: 206 of 241 patients (85%) healed in the open-label phase then randomised to double-blind maintenance.
• Who: adults with endoscopically healed erosive oesophagitis.
• How long: up to 1 year of double-blind maintenance after 8 weeks open-label healing.
• Result: 67% of lansoprazole-treated versus 13% of ranitidine-treated patients remained healed at 1 year (P<0.001)
• Funding: industry-funded (a phase III trial of the manufacturer's product; the record lists Research Support, Non-U.S. Gov't)

At 1 year, 67% of lansoprazole-treated and 13% of ranitidine-treated patients remained healed (P<0.001).

For functional dyspepsia, a use lansoprazole is not approved for, Cochrane found PPIs slightly better than placebo with a number needed to treat of 11. (Source 5)

• Systematic review, Moderate certainty.
• Size: 6,172 participants across 18 trials for the placebo comparison (25 RCTs, 8,453 participants in all)
• Who: adults (16 years or older) with functional dyspepsia diagnosed by validated criteria.
• How long: trials of at least two weeks' duration.
• Result: RR 0.88 (95% CI 0.82 to 0.94) for persisting dyspepsia symptoms; NNTB 11; moderate quality evidence.
• Funding: not stated; the record lists Research Support, Non-U.S. Gov't.

Limit of this finding: The review pooled every proton pump inhibitor together and, because it found low-dose and standard-dose PPIs similarly effective, pooled the dose subgroups too ("Low-dose PPIs had similar efficacy as standard-dose PPIs, therefore we combined these subgroups for the analysis"). The estimate is therefore a class-wide, dose-blind figure; no lansoprazole-specific or dose-specific conclusion can be drawn from it.

PPI was more effective than placebo at relieving overall dyspepsia symptoms in people with FD (risk ratio (RR) 0.88, 95% confidence interval (CI) 0.82 to 0.94; participants = 6172; studies = 18; number needed to treat for an additional beneficial outcome (NNTB) 11; moderate quality evidence).

What the evidence does not support

The same Cochrane review found no clear benefit of PPIs over H2-receptor antagonists for functional dyspepsia. (Source 5)

• Systematic review, Low certainty.
• Size: 740 participants across 2 trials.
• Who: adults with functional dyspepsia.
• How long: trials of at least two weeks' duration.
• Result: RR 0.88 (95% CI 0.74 to 1.04); low quality evidence.
• Funding: not stated; the record lists Research Support, Non-U.S. Gov't.

Limit of this finding: The review pooled every proton pump inhibitor together and, because it found low-dose and standard-dose PPIs similarly effective, pooled the dose subgroups too ("Low-dose PPIs had similar efficacy as standard-dose PPIs, therefore we combined these subgroups for the analysis"). The estimate is therefore a class-wide, dose-blind figure; no lansoprazole-specific or dose-specific conclusion can be drawn from it.

PPIs may have little or no effect compared with H2RAs (RR 0.88, 95% CI 0.74 to 1.04; participants = 740; studies = 2; low quality evidence)

In the largest placebo-controlled randomised trial of long-term PPI treatment, three years of a PPI did not raise pneumonia, fracture, kidney disease, dementia, cancer or death, and the only signal was a small excess of enteric infection. (Source 24)

• Randomized trial, Moderate certainty.
• Size: 17,598 participants (8,791 pantoprazole, 8,807 placebo); 53,152 patient-years of follow-up.
• Who: people with stable cardiovascular disease and peripheral artery disease, also randomised to rivaroxaban and/or aspirin.
• How long: median 3.01 years.
• Result: enteric infections 1.4% versus 1.0% on placebo (odds ratio 1.33; 95% CI 1.01-1.75), an absolute excess of about 0.4 percentage points; no statistically significant difference for any other safety outcome; C difficile infection about twice as common but only 13 events and not statistically significant.
• Funding: not stated in the abstract; the record lists Research Support, Non-U.S. Gov't. The trial drug was pantoprazole, not lansoprazole, so this is class evidence for PPIs rather than a lansoprazole trial.

There was no statistically significant difference between the pantoprazole and placebo groups in safety events except for enteric infections (1.4% vs 1.0% in the placebo group; odds ratio, 1.33; 95% confidence interval, 1.01-1.75). For all other safety outcomes, proportions were similar between groups except for C difficile infection, which was approximately twice as common in the pantoprazole vs the placebo group, although there were only 13 events, so this difference was not statistically significant.

The trial usually cited for proton pump inhibitor rebound symptoms does not test lansoprazole: it gave 120 healthy volunteers esomeprazole 40 mg a day for eight weeks, so on its own it cannot show that lansoprazole does this. (Source 25)

• Randomized trial, Moderate certainty.
• Size: 120 healthy volunteers.
• Who: healthy volunteers with no acid-related diagnosis.
• How long: 12 weeks of placebo, or 8 weeks of esomeprazole 40 mg/d followed by 4 weeks with placebo.
• Result: the drug tested was esomeprazole 40 mg/d for 8 weeks, then 4 weeks of placebo; no lansoprazole arm existed.
• Funding: not stated; the record lists Research Support, Non-U.S. Gov't.

Limit of this finding: This trial used esomeprazole 40 mg daily, not lansoprazole. Reading it across to lansoprazole is a class extrapolation: rebound acid hypersecretion is thought to be a property of acid suppression generally, but it has not been demonstrated for lansoprazole specifically in a trial of this design.

A randomized, double-blind, placebo-controlled trial with 120 healthy volunteers was conducted. Participants were randomized to 12 weeks of placebo or 8 weeks of esomeprazole 40 mg/d followed by 4 weeks with placebo.

A systematic review of acid-output studies concluded there is no strong evidence that acid production rises to a clinically relevant degree after stopping a PPI. (Source 26)

• Systematic review, Low certainty.
• Size: 8 studies, sample size 6-32 each.
• Who: people studied with basal and stimulated acid output after PPI withdrawal.
• How long: PubMed, Embase and Central searched up to October 2005.
• Result: five studies, including four randomised, found no evidence for rebound acid hypersecretion; the three suggestive studies were uncontrolled and the signal was confined to H. pylori-negative subjects after 8 weeks.
• Funding: not stated.

There is some evidence from uncontrolled trials for an increased capacity to secrete acid in H. pylori-negative subjects after 8 weeks of treatment. There is no strong evidence for a clinically relevant increased acid production after withdrawal of proton pump inhibitor therapy.

Cochrane also recorded that there were not enough data to judge the long-term benefits and harms of stopping a PPI. (Source 27)

• Systematic review, Low certainty.
• Size: six trials, 1,758 participants.
• Who: adult chronic PPI users with mild gastro-oesophageal reflux disease.
• How long: not stated.
• Result: no long-term estimate could be produced; only two trials reported endoscopic findings at study end.
• Funding: not stated.

There were insufficient data to make a conclusion regarding long-term benefits and harms of PPI discontinuation, although two trials (one on-demand trial and one abrupt discontinuation trial) reported endoscopic findings in their intervention groups at study end.

The same Cochrane review found no difference in the overall number of adverse events between PPIs and any comparator, and fewer adverse events when a PPI was added to a prokinetic than with the prokinetic alone. (Source 5)

• Systematic review, Moderate certainty.
• Size: 25 RCTs with 8,453 participants in total; 407 participants across 2 trials for the combination comparison.
• Who: adults (16 years or older) with functional dyspepsia diagnosed by validated criteria.
• How long: trials of at least two weeks.
• Result: no differences in the number of adverse events between PPIs and placebo, H2RAs or prokinetics; PPI plus prokinetics versus prokinetics alone RR 0.60 (95% CI 0.39 to 0.93; participants = 407; studies = 2; moderate quality evidence)
• Funding: not stated in the abstract.

Limit of this finding: What the review compared is "the number of adverse events observed", not the rate of any particular one. It is therefore not evidence that any specific harm of a proton pump inhibitor is absent or no more common - only that the trials recorded no difference in how many events happened in total.

There were no differences in the number of adverse events observed between PPIs and any of the other treatments. There were fewer adverse events in the combination of PPI plus prokinetics compared to prokinetics alone (RR 0.60, 95% CI 0.39 to 0.93; participants = 407; studies = 2; moderate quality evidence).

Where the evidence is mixed

The review's own conclusion was that lansoprazole and the other newer proton pump inhibitors matched omeprazole on heartburn control, healing and relapse, and that all the proton pump inhibitors beat ranitidine and placebo at healing erosive oesophagitis. (Source 28)

• Meta-analysis, Moderate certainty.
• Size: 53 studies identified, of which 38 involved acute therapy and 15 maintenance therapy.
• Who: adults with endoscopically assessed erosive oesophagitis in randomised trials.
• How long: 8 weeks for healing; 1 year for relapse.
• Result: no new figures in the conclusion; it summarises the 8-week healing rate ratios of 1.02 (95% CI, 0.98-1.06) against omeprazole 20 mg/d and 1.62 (95% CI, 1.46-1.76) against ranitidine 300 mg/d reported in the results.
• Funding: not stated in the abstract; the record lists Research Support, Non-U.S. Gov't.

Limit of this finding: "Similar efficacy to omeprazole" is a statement of equivalence, not of advantage: lansoprazole did not heal more people than omeprazole. The advantage the review found was over ranitidine and over placebo.

In this study, the newer PPIs were of similar efficacy to omeprazole in terms of heartburn control, healing rates, and relapse rates. All the PPIs were superior to ranitidine and placebo in healing erosive esophagitis and decreasing relapse rates.

For preventing recurrent gastric ulcer in long-term NSAID users without H. pylori, lansoprazole beat placebo but did not beat full-dose misoprostol. (Source 4)

• Randomized trial, Moderate certainty.
• Size: 537 patients.
• Who: patients without H. pylori who were long-term NSAID users with a history of endoscopically documented gastric ulcer.
• How long: 12 weeks, with endoscopy at 4, 8 and 12 weeks.
• Result: gastric ulcer-free at week 12: placebo 51% (95% CI 41.1%-61.3%); misoprostol 93% (95% CI 87.2%-97.9%); lansoprazole 15 mg 80% (95% CI 72.5%-87.3%); lansoprazole 30 mg 82% (95% CI 75.0%-89.6%)
• Funding: not stated in the abstract; the record lists Research Support, Non-U.S. Gov't.

By week 12, the percentages of gastric ulcer-free patients were as follows: placebo, 51% (95% confidence interval [CI], 41.1%-61.3%); misoprostol, 93% (95% CI, 87.2%-97.9%); 15-mg lansoprazole, 80% (95% CI, 72.5%-87.3%); and 30-mg lansoprazole, 82% (95% CI, 75.0%-89.6%).

Cochrane found that switching chronic PPI users to on-demand dosing cut pill burden but left more people with uncontrolled reflux symptoms. (Source 6)

• Systematic review, Low certainty.
• Size: six trials, 1,758 participants.
• Who: adult chronic PPI users (28 days or more of daily use) with nonerosive reflux disease or LA grade A or B oesophagitis; mean ages 48-57 except one trial at 73.
• How long: not stated per trial; five trials tested on-demand use and one abrupt discontinuation.
• Result: lack of symptom control RR 1.71 (95% CI 1.31 to 2.21), five trials, n=1653, low quality evidence; PPI pills per week MD -3.79 (95% CI -4.73 to -2.84), four trials, n=1152, moderate quality evidence.
• Funding: not stated.

There was low quality evidence that on-demand use of PPI may increase risk of 'lack of symptom control' compared with continuous PPI use (risk ratio (RR) 1.71, 95% confidence interval (CI) 1.31 to 2.21), thereby favoring continuous PPI use (five trials, n = 1653). There was a clinically significant reduction in 'drug burden', measured as PPI pill use per week with on-demand therapy (mean difference (MD) -3.79, 95% CI -4.73 to -2.84), favoring deprescribing based on moderate quality evidence (four trials, n = 1152).

Where the research disagrees

Whether long-term PPI use causes the harms observational studies have linked it to

• Moayyedi and colleagues, reporting a 17,598-participant randomised trial with 53,152 patient-years, rct: There was no statistically significant difference between the pantoprazole and placebo groups in safety events except for enteric infections (1.4% vs 1.0% in the placebo group; odds ratio, 1.33; 95% confidence interval, 1.01-1.75). (Source 24)
• The FDA-approved PREVACID label, summarising published observational studies, position: Several published observational studies suggest that PPI therapy may be associated with an increased risk for osteoporosis-related fractures of the hip, wrist or spine. The risk of fracture was increased in patients who received high-dose, defined as multiple daily doses, and long-term PPI therapy (a year or longer). (Source 29)

Whether rebound acid hypersecretion after stopping a PPI is clinically real

• Reimer and colleagues, from a placebo-controlled randomised trial of esomeprazole 40 mg daily - a different PPI from lansoprazole - in 120 healthy volunteers, rct: Forty-four percent (26/59) of those randomized to PPI reported > or = 1 relevant, acid-related symptom in weeks 9-12 compared with 15% (9/59; P < .001) in the placebo group. (Source 15)
• Hunfeld and colleagues, from a systematic review of eight acid-output studies, systematic-review: There is no strong evidence for a clinically relevant increased acid production after withdrawal of proton pump inhibitor therapy. (Source 26)

How much

• Reference intake: Dosing is set by the prescriber, not by a reference intake. The FDA-approved label's adult doses range from 15 mg once daily (maintenance of healed duodenal ulcer, NSAID-ulcer risk reduction, symptomatic GERD, maintenance of healed erosive oesophagitis) to 30 mg once daily (gastric ulcer, NSAID-ulcer healing, erosive oesophagitis), recorded here as the manufacturer's position dated 2025-07-08. (Source 30)
• Upper limit: No tolerable upper intake level exists for a drug. The highest label dose in the adult table is 30 mg three times daily inside dual H. pylori therapy; for self-treatment the non-prescription label caps a course at 14 days and tells people not to take more than one course every four months, which is the nearest thing to a ceiling a member will meet. (Source 17)
• Studied: Graham 2002 gave 15 mg or 30 mg of lansoprazole once daily for 12 weeks against placebo and against 200 microg of misoprostol four times a day in long-term NSAID users. (Source 31)
• Studied: Peura 2009 healed people with open-label lansoprazole 30 mg once daily for 8 weeks, then maintained them on 15 mg once daily or ranitidine 150 mg twice daily for up to a year. (Source 23)
• Studied: Caro 2001 pooled trials comparing lansoprazole 30 mg/d with omeprazole 20 mg/d and with ranitidine 300 mg/d. (Source 2)
• Studied: Reimer 2009 gave healthy volunteers esomeprazole 40 mg a day for 8 weeks, then placebo for 4 weeks, to test what happens on stopping a PPI. (Source 25)

A common belief, and what the research shows

The belief: Long-term PPIs cause dementia, kidney failure, pneumonia and fractures, so they should be feared.

What the research shows: The alarm comes almost entirely from observational studies, which cannot separate the drug from the reasons people are prescribed it. The one adequately powered randomised test, 17,598 people followed a median of 3.01 years, found that “There was no statistically significant difference between the pantoprazole and placebo groups in safety events except for enteric infections (1.4% vs 1.0% in the placebo group; odds ratio, 1.33; 95% confidence interval, 1.01-1.75).” The real, documented downsides of long use are narrower: lower vitamin B12 and iron on observational data, rare low magnesium, and difficulty stopping once started, where “Forty-four percent (26/59) of those randomized to PPI reported > or = 1 relevant, acid-related symptom in weeks 9-12 compared with 15% (9/59; P < .001) in the placebo group.”

Questions and answers

What is it?

Lansoprazole is a proton pump inhibitor, one of a group of substituted benzimidazole drugs that switch off the acid pump in the stomach lining. It is taken by mouth as a delayed-release capsule or an orally disintegrating tablet, and a lower-strength version is sold without prescription for frequent heartburn. It is not a nutrient and the body does not make it. (Source 1)

What does it do in the body?

It blocks the enzyme that pumps acid into the stomach, so much less acid is made whatever is stimulating it. That lowers acid injury to the oesophagus and stomach lining, which is how ulcers and reflux oesophagitis heal. It does not block histamine or acetylcholine receptors. (Source 1)

Is it good or bad for you?

For healing erosive oesophagitis and ulcers, and for keeping them healed, randomised trials show clear benefit: maintenance with lansoprazole kept 67% of people healed at one year against 13% on ranitidine. The picture is different for long, open-ended use with no active disease, where the benefit is unproven and the drawbacks accumulate. So it is useful in a defined course for a defined problem, and much weaker as an indefinite habit. (Source 23)

How do you get more of it?

Lansoprazole is only obtained as a medicine. The prescription product is taken once daily at 15 mg or 30 mg depending on the condition, and a 15 mg non-prescription version is taken once daily for a 14-day course. There is no food or supplement source, and the trials that established its effect gave fixed daily doses rather than anything a person could add from diet. (Source 32)

If it is harmful, what reduces it?

Reducing exposure means taking less of the drug or stopping it, which is a prescriber's decision. Cochrane's deprescribing review found that switching chronic users to on-demand dosing cut pill use by about 3.8 pills a week but left more people with uncontrolled symptoms, so the trade-off is real rather than one-sided. A randomised trial in healthy volunteers also found new acid symptoms appearing after an eight-week course was stopped. (Source 6)

Why might someone be low in it or missing it?

This question does not apply in the usual sense, because lansoprazole is a drug rather than something the body holds a store of. The practical equivalent is that the label itself sets limits on how long it should be used: the non-prescription version tells people to stop and ask a doctor if they need it for more than 14 days or more than one course every four months, and also if they get diarrhoea or develop a rash or joint pain. (Source 17)

Which whole foods contain it or feed it?

No whole food contains lansoprazole. What food does matter for is absorption of other things while acid is suppressed: the label lists iron salts among drugs whose absorption lansoprazole can reduce because it raises stomach pH, and observational studies have linked long-term acid suppression to iron-deficiency anaemia and to low vitamin B12. (Source 7)

What happens if you do not have it?

Not taking lansoprazole is the normal state for most people and causes nothing. For someone with erosive oesophagitis it means a much higher chance of the damage coming back: in the maintenance trial only 13% of people on ranitidine instead of lansoprazole were still healed at a year. For a healthy person who has just finished a course, stopping can bring on heartburn or regurgitation that was not there before: a randomised trial of esomeprazole 40 mg daily, a different PPI, found this in about 44% of volunteers against 15% on placebo. (Source 15)

How can you test for it?

There is no routine blood test for lansoprazole itself in ordinary care, and none of the sources we read describes one. What is monitored instead is the consequences: the label suggests considering magnesium and calcium measurement before starting and periodically in people at risk, and considering vitamin B12 deficiency if symptoms appear after long use. Endoscopy, not a drug level, is what the trials used to judge whether treatment was working. (Source 10)

We searched: We searched PubMed via eutils for lansoprazole monitoring and therapeutic drug levels alongside the rebound, deprescribing and safety literature, and read the full DailyMed SPL for PREVACID; no validated clinical assay for lansoprazole exposure is described in any of them.

References

1. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 12.1 Mechanism of Action (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
2. Clinical Therapeutics. Healing and relapse rates in gastroesophageal reflux disease treated with the newer proton-pump inhibitors lansoprazole, rabeprazole, and pantoprazole compared with omeprazole, ranitidine, and placebo: evidence from randomized clinical trials.. 2001. PMID 11519776, DOI 10.1016/s0149-2918(01)80087-4. Read the source
3. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID (lansoprazole) delayed-release capsules / PREVACID SOLUTAB delayed-release orally disintegrating tablets - Highlights section 1 INDICATIONS AND USAGE (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
4. Archives of Internal Medicine. Ulcer prevention in long-term users of nonsteroidal anti-inflammatory drugs: results of a double-blind, randomized, multicenter, active- and placebo-controlled study of misoprostol vs lansoprazole.. 2002. PMID 11802750, DOI 10.1001/archinte.162.2.169. Read the source
5. Cochrane Database of Systematic Reviews. Proton pump inhibitors for functional dyspepsia.. 2017. PMID 29161458, DOI 10.1002/14651858.CD011194.pub3. Read the source
6. Cochrane Database of Systematic Reviews. Deprescribing versus continuation of chronic proton pump inhibitor use in adults.. 2017. PMID 28301676, DOI 10.1002/14651858.CD011969.pub2. Read the source
7. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 7 DRUG INTERACTIONS, Table 2 (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
8. Family Practice. Is use of a long-term proton pump inhibitor or histamine-2 receptor antagonist a risk factor for iron-deficiency anaemia in Taiwan? A neglected clinical drug-drug interaction (BACKGROUND section).. 2025. PMID 37756627, DOI 10.1093/fampra/cmad090. Read the source
9. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 5.7 Cyanocobalamin (Vitamin B12) Deficiency (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
10. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 5.8 Hypomagnesemia and Mineral Metabolism (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
11. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 7 DRUG INTERACTIONS, Table 2, Warfarin and Methotrexate rows (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
12. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 12.3 Pharmacokinetics, Absorption (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
13. DailyMed (US National Library of Medicine), label of record from Takeda Pharmaceuticals America. PREVACID / PREVACID SOLUTAB prescribing information, section 7 DRUG INTERACTIONS, scope statement and Table 2 caption (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
14. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 5.10 Interaction with Methotrexate (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
15. Gastroenterology. Proton-pump inhibitor therapy induces acid-related symptoms in healthy volunteers after withdrawal of therapy.. 2009. PMID 19362552, DOI 10.1053/j.gastro.2009.03.058. Read the source
16. Alimentary Pharmacology & Therapeutics. Systematic review: Rebound acid hypersecretion after therapy with proton pump inhibitors (RESULTS section).. 2007. PMID 17229219, DOI 10.1111/j.1365-2036.2006.03171.x. Read the source
17. L. Perrigo Company, via DailyMed (US National Library of Medicine). Prevacid 24HR (lansoprazole) delayed-release capsules, OTC Drug Facts, Warnings (SPL set id 205c9c1e-b422-4e86-a4b0-714b608adc19, effective 2025-06-24). 2025. Read the source
18. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 6.1 Clinical Trials Experience (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
19. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, Highlights section 5 WARNINGS AND PRECAUTIONS (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
20. JAMA. Proton pump inhibitor and histamine 2 receptor antagonist use and vitamin B12 deficiency.. 2013. PMID 24327038, DOI 10.1001/jama.2013.280490. Read the source
21. Family Practice. Is use of a long-term proton pump inhibitor or histamine-2 receptor antagonist a risk factor for iron-deficiency anaemia in Taiwan? A neglected clinical drug-drug interaction.. 2025. PMID 37756627, DOI 10.1093/fampra/cmad090. Read the source
22. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 5.2 Acute Tubulointerstitial Nephritis (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
23. Digestive Diseases and Sciences. Lansoprazole for long-term maintenance therapy of erosive esophagitis: double-blind comparison with ranitidine.. 2009. PMID 18726153, DOI 10.1007/s10620-008-0466-9. Read the source
24. Gastroenterology. Safety of Proton Pump Inhibitors Based on a Large, Multi-Year, Randomized Trial of Patients Receiving Rivaroxaban or Aspirin.. 2019. PMID 31152740, DOI 10.1053/j.gastro.2019.05.056. Read the source
25. Gastroenterology. Proton-pump inhibitor therapy induces acid-related symptoms in healthy volunteers after withdrawal of therapy.. 2009. PMID 19362552, DOI 10.1053/j.gastro.2009.03.058. Read the source
26. Alimentary Pharmacology & Therapeutics. Systematic review: Rebound acid hypersecretion after therapy with proton pump inhibitors.. 2007. PMID 17229219, DOI 10.1111/j.1365-2036.2006.03171.x. Read the source
27. Cochrane Database of Systematic Reviews. Deprescribing versus continuation of chronic proton pump inhibitor use in adults (AUTHORS' CONCLUSIONS section).. 2017. PMID 28301676, DOI 10.1002/14651858.CD011969.pub2. Read the source
28. Clinical Therapeutics. Healing and relapse rates in gastroesophageal reflux disease treated with the newer proton-pump inhibitors lansoprazole, rabeprazole, and pantoprazole compared with omeprazole, ranitidine, and placebo: evidence from randomized clinical trials.. 2001. PMID 11519776, DOI 10.1016/s0149-2918(01)80087-4. Read the source
29. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 5.4 Bone Fracture (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
30. Takeda Pharmaceuticals America, Inc., via DailyMed (US National Library of Medicine). PREVACID / PREVACID SOLUTAB prescribing information, section 2.1 Recommended Adult Dosage by Indication (SPL set id 71ba78cb-7e46-43eb-9425-fa130f537f84, effective 2025-07-08). 2025. Read the source
31. Archives of Internal Medicine. Ulcer prevention in long-term users of nonsteroidal anti-inflammatory drugs: misoprostol vs lansoprazole (METHODS section).. 2002. PMID 11802750, DOI 10.1001/archinte.162.2.169. Read the source
32. L. Perrigo Company, via DailyMed (US National Library of Medicine). Prevacid 24HR (lansoprazole) delayed-release capsules, OTC Drug Facts, Directions (SPL set id 205c9c1e-b422-4e86-a4b0-714b608adc19, effective 2025-06-24). 2025. Read the source