Side effects of omeprazole
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Side Effects of Omeprazole: A Comprehensive Overview
Common Side Effects of Omeprazole
Omeprazole, a widely used proton pump inhibitor (PPI), is generally well-tolerated but can cause several common side effects. These include gastrointestinal issues such as nausea, diarrhea, constipation, and abdominal pain2 3 5. Additionally, patients may experience headaches and dizziness2 5.
Neurological and Psychiatric Effects
Neurological and psychiatric side effects have been reported, particularly in older patients or those with hepatic diseases. These effects include confusion, dizziness, and headaches2.
Dermatological Reactions
Cutaneous reactions, although less common, can occur and include skin rash, urticaria, and more severe conditions like contact dermatitis, lichenoid eruption, leukocytoclastic vasculitis, and toxic epidermal necrolysis2 3.
Hematological and Hepatic Effects
Hematological side effects such as leucopenia and agranulocytosis have been noted, though their direct relationship with omeprazole is uncertain2. Hepatic side effects include moderate elevations in aminotransferases and, in rare cases, fulminant hepatic failure2 7.
Genomic Instability and Cancer Risk
Long-term use of omeprazole has been associated with an increased risk of gastric cancer due to its potential to induce genomic instability. This risk is particularly concerning given the drug's widespread use for chronic conditions1.
Renal Effects
Omeprazole has been linked to acute interstitial nephritis (AIN), a serious condition that can lead to renal failure. Symptoms of AIN include fatigue, fever, anorexia, and nausea, and it typically resolves upon discontinuation of the drug and initiation of corticosteroid therapy9.
Endocrinologic and Gastrointestinal Effects
Endocrinologic abnormalities such as gynecomastia have been reported, although they are rare3. Gastrointestinal side effects include dry mouth, which can lead to opportunistic infections like Candida albicans due to reduced salivary flow5.
Drug-Drug Interactions
Omeprazole can interact with various medications, affecting their pharmacokinetics and potentially leading to treatment failure or toxicity. Drugs affected include diazepam, carbamazepine, clozapine, and several antiretrovirals, among others. These interactions are often mediated through the cytochrome P450 enzyme system4.
Fundic Gland Polyps
Long-term omeprazole therapy has been associated with the development of fundic gland polyps, particularly in patients without Helicobacter pylori infection. These polyps are generally benign but highlight the need for monitoring during prolonged treatment10.
Conclusion
While omeprazole is effective for treating various gastrointestinal disorders, it is associated with a range of side effects, from common gastrointestinal issues to more severe conditions like genomic instability and acute interstitial nephritis. Patients and healthcare providers should be aware of these potential risks, especially with long-term use, and manage them through appropriate monitoring and alternative therapies when necessary.
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Most relevant research papers on this topic
Pharmacological Effects and Toxicogenetic Impacts of Omeprazole: Genomic Instability and Cancer
Long-term use of omeprazole may induce genomic instability and increase the risk of certain types of cancer, requiring adequate precautions.
Systematic Review
Rigorous Journal[Evaluation of unexpected and toxic effects of omeprazole (Mopral) reported to the regional centers of pharmacovigilance during the first 22 postmarketing months].
Omeprazole is a well-tolerated proton pump inhibitor for treating peptic ulcers, erosive reflux esophagitis, and Zollinger Ellison syndrome, with potential toxicity including confusion, hepatotoxicity, and leucopenia.
[Anaphylaxis caused by omeprazole].
Omeprazole can cause anaphylaxis in rare cases, indicating its importance in monitoring patients with proton pump inhibitor-related side effects.
Case ReportPharmacokinetic drug interaction profile of omeprazole with adverse consequences and clinical risk management
Omeprazole can cause adverse drug interactions with various medications, requiring enhanced clinical risk management to avoid adverse consequences.
Systematic ReviewRigorous Journal
Highly CitedOmeprazole and dry mouth.
Omeprazole treatment can reduce salivary flow, potentially predisposing to opportunistic infections, particularly in the edentulous.
Dose-response study of omeprazole on meal-stimulated gastric acid secretion and gastrin release.
Omeprazole is a potent and well-tolerated inhibitor of meal-stimulated gastric acid secretion in humans, with a 4.5-hour inhibitory effect lasting more than 4.5 hours.
RCTHighly CitedFulminant hepatic failure related to omeprazole.
Omeprazole may cause fulminant hepatic failure in patients with severe reflux esophagitis and Zollinger-Ellison syndrome, highlighting the need for caution in prescribing this drug.
Case ReportEffects of single and repeated doses of omeprazole on gastric acid and pepsin secretion in man.
Omeprazole effectively reduces gastric acid output without causing side effects, while not significantly affecting pepsin secretion.
Non-RCTHighly CitedAcute interstitial nephritis due to omeprazole
Omeprazole use can cause acute interstitial nephritis, with most patients recovering normal renal function after withdrawal and corticosteroid therapy.
Case ReportHighly CitedFundic gland polyps developing during omeprazole therapy.
Omeprazole therapy may cause the development of fundic gland polyps in patients without H. pylori gastritis.
Case ReportHighly Cited