Subacute myopathy during omeprazole therapy

Adverse outcomes of long-term use of proton pump inhibitors: a systematic review and meta-analysis

The association between the long-term use of proton pump inhibitors (PPIs) and the risks of various diseases remains controversial. Therefore, the primary objective of this study was to quantify the associations as presented in the literature and to also provide this information to healthcare professionals and patients about their potentially adverse effects. In July 2016, we searched through Medline (PubMed), Embase, and the Cochrane Library from inception using common keywords. We included observational studies that provided risk estimates on the long-term use of PPIs and their adverse effects. Overall, 43 studies were included in the systematic review, of which 28 studies were also included in the random effect meta-analysis. Odds of community-acquired pneumonia, hip fracture, and colorectal cancer were 67% [odds ratio (OR)=1.67; 95% confidence interval (CI): 1.04-2.67], 42% (OR=1.42; 95% CI: 1.33-1.53), and 55% (OR=1.55; 95% CI: 0.88-2.73) higher in patients with long-term PPIs use compared with patients who did not use PPIs. Although the use of PPIs provides short-term health benefits, their prolonged use is associated with minor and also potentially major adverse health outcomes. Hence, we strongly recommend that the prescription of PPIs should be done with caution to improve the medication's efficacy and patients' safety.

Proton Pump Inhibitors: Risk for Myopathy?

OBJECTIVE

The purpose of this article is to describe the relationship between proton pump inhibitors (PPIs) and symptoms of myopathy based on case reports.

DATA SOURCES

A literature search was conducted in PubMed (1946 to June 2016) using MeSH terms proton pump inhibitors, omeprazole, esomeprazole, lansoprazole, dexlansoprazole, rabeprazole, pantoprazole, and muscular diseases. Additionally, a search was conducted in ToxNet and EMBASE using similar search criteria.

STUDY SELECTION AND DATA ABSTRACTION

The resulting articles were scanned to assess relevance to the review. Bibliographies of all relevant articles were evaluated for additional sources; 26 articles resulted from the search of PubMed, ToxNet, and EMBASE; articles that involved medications typically considered to have myalgia-like side effects (eg, statins), or included patients who presented with a confounding disease state (eg, Guillain-Barré) were excluded.

DATA SYNTHESIS

In total, 11 case reports as well as a review of an adverse event reporting database that included 292 cases were evaluated. Association of PPI use and myopathy symptoms does not have a clear etiology. Overall, the available published data do not show a high risk of myopathy with PPI use but should be considered if a patient presents with myopathy symptoms and concurrent PPI use.

CONCLUSION

A limited body of published data suggests that PPI use has been associated with myopathy-like symptoms without long-term effects following discontinuation. Although myopathy is a rare adverse effect observed with PPIs, it can be a serious side effect to be considered when starting a patient on acid suppression therapy.

Toxic myopathies

Muscle tissue is highly sensitive to many substances. Early recognition of toxic myopathies is important, because they potentially are reversible on removal of the offending drug or toxin, with greater likelihood of complete resolution the sooner this is achieved. Clinical features range from mild muscle pain and cramps to severe weakness with rhabdomyolysis, renal failure, and even death. The pathogenic bases can be multifactorial. This article reviews some of the common toxic myopathies and their clinical presentation, histopathologic features, and possible underlying cellular mechanisms.

Transmucosal gastric leak induced by proton pump inhibitors

Despite their remarkable safety profile and lack of clinical side effects, proton pump inhibitors (PPIs) induce a transmucosal gastric leak to non-electrolyte probes of various sizes. The ex vivo addition of PPIs to isolated rat gastric corpus increases transmucosal permeability in a dose-dependent manner, which corresponds with PPIs' dose-dependent inhibition of acid secretion. Upon the addition of omeprazole, lansoprazole, or esomeprazole, a small decrease in transepithelial resistance and the concomitant stimulation of short circuit current was observed. Additionally, transepithelial flux of (14)C-[D]-mannitol (MW 182.17) across the gastric mucosa increased by a mean of 68% immediately following the addition of 200 microM omeprazole. This flux increase was bidirectional. Omeprazole also increased the paracellular permeability to larger radiolabeled probes, including (14)C-sucrose (MW 342.3) and (14)C-polyethylene glycol (MW 4,000) by 118% and 350%, respectively. However, the flux of still larger probes, 10,000 and 70,000 MW dextrans, was not increased. Because PPIs are so widely used and are assumed to be innocuous, this transmucosal gastric leak must be further investigated, as it may carry considerable biomedical implications.

Myopathy including polymyositis: a likely class adverse effect of proton pump inhibitors?

OBJECTIVE

Polymyositis occurring in patients treated with omeprazole has been signalled as a possible adverse drug reaction (ADR) by the New Zealand Intensive Medicines Monitoring Programme (IMMP) and the WHO Collaborating Centre for International Drug Monitoring: the Uppsala Monitoring Centre (UMC). Polymyositis and other myopathies have also been reported in post-marketing data and in the medical literature in association with proton pump inhibitor (PPI) use. We wished to follow-up these signals and investigate the evidence of causality for the association of polymyositis and other myopathy with PPI use.

METHODS

Spontaneously reported ADRs from national monitoring centres are sent to the WHO ADR database (VigiBase). VigiBase was searched for case reports of the PPIs, omeprazole, pantoprazole, lansoprazole, esomeprazole and rabeprazole, with terms indicative of myopathy, and further information was elicited from the national centres to help establish causality. Literature sources were reviewed for the occurrence of the above terms in combination with PPIs.

RESULTS

In total, there were 292 reports of various myopathies with PPIs, excluding 868 cases of 'myalgia'. In this analysis, 69 patients recovered when the drug was withdrawn and, in 15 patients, the reaction re-occurred when the drug was reinstated. In one-third of the 292 cases, the PPI was the single administered drug, and the PPI was the single suspected drug by the reporter in 57% of reports where concomitant medication was used. In this analysis, three index cases are documented. One involves the same patient taking three different PPIs (lansoprazole, esomeprazole and rabeprazole) at different time periods, with myalgia and muscle weakness occurring with all three drugs. In the two other index cases, myopathies with esomeprazole and omeprazole were reported with positive rechallenge, and causality was assessed as 'possible' and 'certain' by the reporting centres. In 27 cases myositis or polymyositis was reported. Other myopathies were reported, including 35 cases with rhabdomyolysis. In 9 of these cases, the PPI was withdrawn and the reaction abated. The PPI was reinstated in one patient, but the reaction did not re-occur. Time to onset was given in 17 of the rhabdomyolysis cases, rhabdomyolysis occurred with the first week in 9 cases, and in 3 cases the reaction occurred between 14 days to 3 months of treatment. In 12 of these patients, an HMG-CoA reductase inhibitor (statin) was taken concomitantly.

CONCLUSION

Case reports from the WHO ADR database, including index cases involving four out of five PPIs, along with evidence of a possible mechanism, provide compelling evidence that there is a causal association between members of the PPI drug class and myopathy including polymyositis. Evidence was also obtained to support the view that PPI use may be associated with occurrence of other myopathies, including the serious reaction rhabdomyolysis.

Toxic Myopathies

Muscle tissue is highly sensitive to drugs and toxins because ot its high metabolic activity and potential sites for disruption of energy-producing pathways. Early recognition of toxic myopathies is important, as they potentially are reversible on removal of the offending toxin, with greater likelihood of complete resolution the sooner this is achieved. Clinical features range from mild muscle pain and cramps to severe weakness with rhabdomyolysis, renal failure, and even death. The pathogenic bases can be multifactorial. This article reviews drugs responsible for common types of toxic myopathy and their clinical and histopathologic features and illustrates possible underlying cellular mechanisms.

The rates of common adverse events reported during treatment with proton pump inhibitors used in general practice in England: cohort studies

AIMS

To estimate the rates of common adverse events in patients treated with the proton pump inhibitors omeprazole, lansoprazole and pantoprazole in general practice in England.

METHODS

In prescription-event monitoring cohort studies, data on dispensed prescriptions prescribed by general practitioners in England soon after each drug was launched were linked to subsequent clinical events recorded by the prescriber. 16 205 patients prescribed omeprazole between June 1989 and June 1990, 17 329 patients prescribed lansoprazole between May and November 1994, and 11 541 patients prescribed pantoprazole between December 1996 and June 1997 were studied.

RESULTS

The commonest adverse events in the omeprazole, lansoprazole and pantoprazole cohorts were diarrhoea (incidence: 0. 18, 0.39 and 0.23 per 1000 days of exposure, respectively); nausea/vomiting (incidence: 0.16, 0.22 and 0.18 per 1000 days of exposure, respectively); abdominal pain (incidence: 0.17, 0.21 and 0. 17 per 1000 days of exposure, respectively); and headache (incidence rates: 0.10, 0.17 and 0.15 per 1000 days of exposure, respectively). The remaining adverse events occurred at rates of less than 0.11 per 1000 days of exposure. There were little absolute differences in the rates of most events between the three proton pump inhibitors. However, diarrhoea was more commonly associated with lansoprazole compared with omeprazole (rate difference: 0.21 per 1000 days of exposure; 95% CI 0.17, 0.25; rate ratio: 2.11; 1.78, 2.51), and there was a clear age-response relationship.

CONCLUSIONS

Adverse events occurred relatively infrequently in all three cohorts. There were only small absolute differences in event rates between the three drugs, although these data suggest the hypothesis that lansoprazole is associated with more frequent occurrence of diarrhoea, particularly in the elderly.

Omeprazole. An update of its pharmacology and therapeutic use in acid-related disorders

Omeprazole, a gastric acid pump inhibitor, dose-dependently controls gastric acid secretion: the drug has greater antisecretory activity than histamine H2-receptor antagonists. Omeprazole 20 to 40 mg/day is more effective than histamine H2-receptor antagonists in the short term treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis. Available data suggest that omeprazole 10 to 40 mg/day is also more effective than ranitidine in the maintenance therapy of duodenal ulcer and reflux oesophagitis. The drug is also effective in patients with duodenal ulcer, gastric ulcer or reflux oesophagitis poorly responsive to histamine H2-receptor antagonists. The efficacy of omeprazole 20 mg/day appears to be similar to that of lansoprazole 30 mg/day in the short term treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis. However, most available studies have been reported in abstract form only, and 2 of 3 studies in patients with duodenal ulcer have shown greater healing rates at 2 (but not 4) weeks with lansoprazole. Helicobacter pylori eradication decreases duodenal ulcer relapse rates and appears to be associated with improved duodenal ulcer healing rates. Evidence also suggests that H. pylori eradication is associated with reduced gastric ulcer relapse rates. Omeprazole monotherapy may suppress but does not eradicate H. pylori infection. Eradication rates with omeprazole 20 or 40 mg twice daily plus amoxicillin usually up to 2 g/day (3 g/day in a few studies) for 2 weeks appear to be similar to those of standard triple therapy (bismuth salt plus metronidazole, plus tetracycline or amoxicillin) or omeprazole plus clarithromycin, although eradication rates vary widely. Omeprazole plus amoxicillin appears to be better tolerated than triple therapy and represents a first-line treatment alternative in patients with H. pylori-associated peptic ulcer disease. Omeprazole plus amoxicillin plus metronidazole appears to be more effective than omeprazole plus amoxicillin in patients with metronidazole-sensitive H. pylori infection. Omeprazole remains a treatment of choice in patients with Zollinger-Ellison syndrome. The dosages should be adjusted according to individual response. However, relatively low dosages of 10 to 40 mg/day may be sufficient in some patients. The drug has also shown promise in the treatment of children with severe reflux oesophagitis, in patients with reflux oesophagitis and coexisting systemic sclerosis, and in the prevention of aspiration pneumonia. Evidence suggests that omeprazole is more effective than ranitidine in patients with nonsteroidal anti-inflammatory drug (NSAID)-induced gastric damage who continue to take NSAIDs, especially in patients with large gastric ulcers; however, completion of ongoing studies is required to verify this.(ABSTRACT TRUNCATED AT 400 WORDS)