Can iron pills cause constipation
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Can Iron Pills Cause Constipation?
Iron deficiency anemia (IDA) is a prevalent health issue globally, and oral iron supplementation is a common treatment. However, one of the significant side effects associated with iron pills is constipation. This article explores the relationship between iron supplementation and constipation, drawing on multiple research studies.
Gastrointestinal Side Effects of Iron Pills
Common Side Effects: Constipation and Bloating
Iron supplements, particularly those containing ferrous sulfate, are known to cause gastrointestinal side effects. These include nausea, vomiting, diarrhea, and notably, constipation and bloating1 3 5. A study assessing the side effects of ferrous sulfate and an alternative iron source, Aspergillus oryzae, found that ferrous sulfate caused a higher incidence of gastrointestinal discomfort, including constipation1.
Methanogenesis and Constipation
Recent research has linked iron supplementation to increased methane production in the gut, which can slow down gut transit and lead to constipation. Methane production is facilitated by methanogenic archaea, which require iron for their enzymatic pathways2 5. A study involving 396 patients found that those taking iron supplements had significantly higher methane production, correlating with increased constipation2.
Impact on Compliance
Reduced Adherence Due to Side Effects
The side effects of iron pills, including constipation, significantly impact patient compliance. Pregnant women, in particular, often discontinue iron supplementation due to these adverse effects, which can lead to persistent iron deficiency3 4. A systematic review highlighted that the negative side effects of iron tablets, such as constipation, reduce adherence to the supplementation regimen among pregnant women3.
Alternative Iron Supplements
To mitigate these side effects, alternative iron supplements have been explored. For instance, a combination of heme and non-heme iron has been shown to cause fewer gastrointestinal issues compared to traditional non-heme iron supplements8. Additionally, lower doses and different formulations, such as every other day dosing, have been suggested to reduce side effects while maintaining efficacy7 9.
Conclusion
Iron pills can indeed cause constipation, a side effect that significantly affects patient compliance with iron supplementation regimens. The relationship between iron intake and increased methane production in the gut provides a potential explanation for this side effect. Exploring alternative iron formulations and dosing strategies may help mitigate these adverse effects and improve adherence to iron supplementation, ultimately addressing iron deficiency more effectively.
Sources and full results
Most relevant research papers on this topic
Assessment of Gastrointestinal Symptoms and Non-transferrin Bound Iron After Oral Ferrous Sulfate and Iron-enriched Aspergillus Oryzae Supplementation in Women (P24-039-19).
ULT is a safer oral iron supplement for treating iron deficiency anemia with better compliance and less gastrointestinal side effects compared to FeSO4, maintaining normal iron status.
RCT
Very Rigorous JournalPWE-055 Iron supplementation, microbiome related methanogenesis and constipation – novel model to explain an age-old problem
Oral iron supplementation may increase gut microbiome methanogenesis, leading to constipation in some patients.
Observational Study
Rigorous JournalThe effect of iron tablets' side effects on the level of compliance to consuming iron tablets in pregnant woman: A systematic review
Pregnant women's compliance to iron supplementation decreases due to negative side effects and lack of information from health professionals about iron tablets and their benefits.
Systematic ReviewHUBUNGAN MENGKONSUMSI TABLET FE DENGAN KEJADIAN KONSTIPASI PADA IBU HAMIL DI DESA BANDAR KECAMATAN BANDAR KABUPATEN PACITAN
Consuming iron tablets regularly during pregnancy is associated with increased constipation in 54.50% of women studied in Bandar Village, Pacitan.
Observational StudyOral Iron Supplementation—Gastrointestinal Side Effects and the Impact on the Gut Microbiota
Oral iron supplementation may cause gastrointestinal side effects due to changes in gut microbiota, potentially linked to increased intestinal methane production and slowing intestinal transit.
Literature ReviewIleus Due to Iron Pills: A Case Report and Literature Report on the Importance of Stool Softeners
Iron pills can cause ileus secondary to bowel obstruction due to constipation, highlighting the importance of stool softeners for patients with iron deficiency anemia.
Case ReportRigorous JournalThe role of oral iron in the treatment of adults with iron deficiency
Oral iron supplementation is often the first-line treatment for iron deficiency, but optimal formulation and dosing strategies remain unclear, with potential for side effects and gastrointestinal limitations.
Rigorous JournalSide effects of iron supplements in blood donors: superior tolerance of heme iron.
Hemofer, a low-dose iron supplement containing both heme and non-heme iron, has fewer side effects compared to traditional non-heme iron supplements in blood donors.
RCTThe role of oral iron in the treatment of adults with iron deficiency
Oral iron supplementation is often the first-line treatment for iron deficiency, but optimal formulation and dosing strategies remain unclear, and further study is needed to advance care for individuals affected by iron deficiency.
The Effect of High Dosage of Iron Supplementation (Fe) Against Histopathology of Gastric Mucosa in Pregnant Strain Wistar White Rats (Rattus norvegicus)
High doses of iron supplementation during pregnancy can cause damage to the gastric mucosa in pregnant Wistar white rats.
RCT