{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T21:21:57Z","timestamp":1790976117045,"version":"4.1.0"},"reference-count":38,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T00:00:00Z","timestamp":1769126400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Pharmacol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>The relationship between oral iron preparation-related gastrointestinal adverse events (AEs) and medication adherence in female patients with iron deficiency anemia (IDA) remains unclear.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>To assess gastrointestinal AEs linked to oral iron preparations via the US FDA Adverse Event Reporting System (FAERS), evaluate medication adherence levels in female IDA patients, and analyze the impact of gastrointestinal AEs and other factors on their medication adherence.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Reporting odds ratio (ROR) and Proportional Reporting Ratio (PRR) were used to analyze oral iron preparation-related gastrointestinal AEs. The Medication Adherence Report Scale-5 (MARS-5) was used to assess patients\u2019 medication adherence, while logistic regression analyzed the impact of factors (gastrointestinal AEs, medication beliefs, illness perception, doctor-patient relationship, social support) on medication adherence.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>FAERS recorded 2,624 reports of gastrointestinal AEs following oral iron supplementation in female patients with IDA (January 2000\u2013March 2025). Disproportionality analysis indicated that ferrous fumarate exhibited the weakest gastrointestinal AE disproportional reporting signal (ROR = 0.36, 95% CI 0.27\u20130.48; PRR = 0.44), with no positive signals detected, whereas ferrous gluconate displayed the strongest signal (ROR = 2.62, 95% CI 2.05\u20133.34; PRR = 1.90) and the most prominent positive signals. No significant gastrointestinal AE disproportional reporting signals were found for ferrous sulfate or iron polysaccharide complex. A cross-sectional study (148 patients) showed that adherent patients and non-adherent patients accounted for 64.86% and 35.14%, respectively. Multivariate logistic regression analysis indicated that gastrointestinal AEs were not significantly associated with medication adherence, while medication concern beliefs, doctor-patient relationship, and hemoglobin level were important factors affecting medication adherence in female IDA patients.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Gastrointestinal AEs are not a key factor affecting medication adherence. Reducing patients\u2019 medication concerns, improving the doctor-patient relationship and reinforcing counseling to avoid premature medication withdrawal due to elevated hemoglobin levels are beneficial to enhancing medication adherence in female IDA patients.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fphar.2026.1727566","type":"journal-article","created":{"date-parts":[[2026,1,23]],"date-time":"2026-01-23T06:45:00Z","timestamp":1769150700000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":5,"title":["Oral iron preparations: gastrointestinal adverse events and medication adherence in female patients with iron deficiency anemia"],"prefix":"10.3389","volume":"17","author":[{"given":"Xing","family":"Tan","sequence":"first","affiliation":[{"name":"Fujian University of Traditional Chinese Medicine","place":["Fuzhou, China"]},{"name":"Department of Hematology, Rudong People\u2019s Hospital and Affiliated Rudong Hospital of Xinglin College, Nantong University","place":["Nantong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Tian","sequence":"additional","affiliation":[{"name":"Rudong Hospital of Traditional Chinese Medicine","place":["Nantong, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tongtong","family":"Zhang","sequence":"additional","affiliation":[{"name":"Fujian University of Traditional Chinese Medicine","place":["Fuzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Qi","family":"Yao","sequence":"additional","affiliation":[{"name":"Department of gynecology, Fuzhou Second General Hospital","place":["Fuzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tingting","family":"Zhu","sequence":"additional","affiliation":[{"name":"Fujian University of Traditional Chinese Medicine","place":["Fuzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wei","family":"Wang","sequence":"additional","affiliation":[{"name":"Fujian University of Traditional Chinese Medicine","place":["Fuzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Quanjie","family":"Wang","sequence":"additional","affiliation":[{"name":"Fujian University of Traditional Chinese Medicine","place":["Fuzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haiying","family":"Fu","sequence":"additional","affiliation":[{"name":"Department of Hematology, The Third Affiliated Hospital of Fujian University of Traditional Chinese Medicine","place":["Fuzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,23]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"2289","DOI":"10.2147\/DMSO.S505605","article-title":"Factors influencing adherence to refills and medications in patients with type 2 diabetes mellitus in Saudi Arabia: a questionnaire-based study","volume":"18","author":"Alnajjar","year":"2025","journal-title":"Diabetes Metab. 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