Omeprazole long term side effects
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Omeprazole Long-Term Side Effects: Overview and Key Risks
Omeprazole is a widely used proton pump inhibitor (PPI) for treating acid-related gastrointestinal conditions. While effective, long-term use has been linked to several adverse effects that require careful consideration.
Hematological and Biochemical Changes from Long-Term Omeprazole Use
Multiple studies have found that prolonged omeprazole use can lead to significant reductions in red blood cell counts and indices, increasing the risk of anemia. There are also notable declines in serum ferritin, vitamin D, and calcium levels, which can contribute to nutrient deficiencies and bone health issues. Additionally, long-term use is associated with elevated cholesterol, triglycerides, low-density lipoprotein (LDL), alkaline phosphatase, aspartate aminotransferase, creatinine, and blood urea levels, indicating potential impacts on liver and kidney function as well as lipid metabolism Ali2022Elkedrawy2024.
Electrolyte and Mineral Imbalances
Long-term omeprazole therapy can cause reductions in serum sodium, calcium, and magnesium, leading to conditions such as hypomagnesemia and hypocalcemia. These imbalances may be asymptomatic but can have serious health consequences if left unchecked, especially in children . Deficiency in vitamin D is also commonly reported among long-term users Elfarrah2025Ali2022.
Renal and Liver Effects
Research in both humans and animal models shows that chronic omeprazole use can impair kidney function, as evidenced by increased creatinine and urea levels, and can cause structural kidney damage through inflammation, fibrosis, and cellular degeneration Ali2022Maher2023Elkedrawy2024. Liver enzyme elevations have also been observed, suggesting possible hepatic stress .
Gastrointestinal and Infection Risks
Long-term omeprazole use is linked to an increased risk of urinary tract infections and gastritis. There is also evidence of confusion and other neurological symptoms in some users . The drug’s impact on the gastrointestinal microbiome may contribute to digestive disturbances and a higher risk of infections Kumar2025Gil-Vicente2024.
Endocrine and Cancer-Related Concerns
Omeprazole can cause moderate increases in serum gastrin levels, which, in animal studies, have been associated with changes in gastric endocrine cells and, at very high doses, the development of carcinoid tumors. However, these effects are less pronounced in humans at therapeutic doses, and long-term studies in patients have not shown significant changes in gastric cell densities or a clear increase in cancer risk at standard doses Arnold1989Maton1989Gil-Vicente2024. Nonetheless, some research suggests a potential link between long-term omeprazole use, genomic instability, and increased cancer risk, warranting further investigation and caution .
Nutrient Absorption and Deficiencies
Chronic omeprazole therapy can impair the absorption of key nutrients, leading to deficiencies in vitamin D, calcium, and possibly cobalamin (vitamin B12), although the latter is less consistently observed in animal studies compared to humans Elfarrah2025Ali2022Kumar2025+1 MORE.
Conclusion
While omeprazole is generally safe and effective for short-term use, long-term therapy is associated with a range of potential side effects, including anemia, nutrient deficiencies, electrolyte imbalances, kidney and liver function changes, increased infection risk, and possible endocrine and cancer-related effects. Regular monitoring and judicious use are recommended, especially for those requiring prolonged treatment.
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Most relevant research papers on this topic
Long-Term Use of Omeprazole: Effect on Haematological and Biochemical Parameters.
Long-term omeprazole use may lead to anemia, disturbances in biochemical profile, and reduced levels of minerals and vitamins due to affected absorption.
Reno-protective Role of Ginseng in Counteracting the Long-term Omeprazole Induced Adverse Effects in Albino Rats via Modulation of Inflammation, Apoptosis and Fibrosis
Ginseng can counteract long-term omeprazole-induced renal damage in albino rats by reducing inflammation, fibrosis, and apoptosis.
Effect of Sub- Chronic Administration of Omeprazole on Hematological and Biochemical Parameters in Fischer Male Rats
Prolonged use of omeprazole may cause adverse effects on hematological profile, leading to anemia, and disturbances in biochemical profile, levels of minerals, and vitamins due to affected absorption.
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.
A Comprehensive Review on Omeprazole: Pharmacological Effects and Its Adverse Effects
Omeprazole is an effective treatment for acid-related gastrointestinal disorders, but its long-term use and potential drug interactions require careful consideration of its adverse effects.
Long-term efficacy and safety of omeprazole in patients with Zollinger-Ellison syndrome: a prospective study.
Omeprazole is a safe and effective long-term treatment for Zollinger-Ellison syndrome, with no evidence of hematologic, biochemical, or gastric toxicity.
Electrolyte disturbances in children receiving omeprazole for gastroesophageal reflux disease
Long-term use of omeprazole in children with gastroesophageal reflux disease may cause asymptomatic hypomagnesemia, hypocalcemia, and hypernatremia, requiring monitoring.
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