Why is there a surge in iron infusions and what are the side effects?

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1. 1

   Iron Deficiency and Iron-Deficiency Anemia Among Reproductive-Age Women in the United States: Prevalence and Disparities, 2015-2023.

   Anemia (Singh et al.)Published Aug 27, 2026Checked Oct 16, 2026

   “ID and IDA were defined using World Health Organization 2020 inflammation-adjusted ferritin thresholds incorporating C-reactive protein. Multivariable logistic regression examined associations between sociodemographic factors and iron status outcomes.ResultsAmong nonpregnant women (n = 3156), 27.4% had ID and 8% had IDA. Among pregnant women (n = 166), 75.5% had ID and 8.3% had IDA. Non-Hispanic Black women had 2.8-fold higher odds of IDA (adjusted odds ratio [aOR] 2.8, 95% CI 1.6, 4.9). Obesity was independently associated with ID (aOR 2.4, 95% CI 1.86, 3.24) in nonpregnant women and pregnant women (aOR 4.5, 95% CI 1.08, 18.76). Racial and ethnic disparities persisted after adjustment for education, income, and food security.ConclusionsID and IDA remain highly prevalent among U.S. reproductive-age women, with substantial and persistent racial, ethnic, and socioeconomic disparities. As a preventable and treatable condition with significant impacts on quality of life and pregnancy outcomes, it warrants greater clinical and public health attention, particularly among non-Hispanic Black women, Hispanic women, women with obesity, and those experiencing socioeconomic disadvantages.”

2. 2

   Intravenous Iron Infusion in Patients with Heart Failure: A Systematic Review and Study-Level Meta-Analysis

   ESC Heart Failure (Salah et al.)Published Feb 2, 2023Checked Oct 16, 2026

   “Outcomes were the composite of CV mortality and first hospitalization for HF; all-cause mortality; CV mortality; first hospitalization for HF; and total hospitalizations for HF. Random effects risk ratio (RR) with 95% confidence intervals (CIs) were calculated. Ten RCTs with a total of 3438 patients were included. Intravenous iron resulted in a significant reduction in the composite of CV mortality and first hospitalization for HF [RR 0.0.85; 95% CI (0.77, 0.95)], first hospitalization for HF [RR 0.82; 95% CI (0.67, 0.99)], and total hospitalizations for HF [RR 0.74; 95% CI (0.60, 0.91)] but no statistically significant difference in all-cause mortality [RR 0.95; 95% CI. (0.83, 1.09)] or CV mortality [OR 0.89; 95% CI (0.75, 1.05)]. Intravenous iron infusion in patients with HF reduces the composite risk of first hospitalization for HF and CV mortality as well as the risks of first and recurrent hospitalizations for HF, with no effect on all-cause mortality or CV mortality alone.”

3. 3

   Intravenous Iron Therapy in Heart Failure With Iron Deficiency: An Umbrella Review of Systematic Reviews and Meta-Analyses.

   Cureus (Kshatri et al.)Published Aug 21, 2026Checked Oct 16, 2026

   “The treatment effect appeared attenuated in the one review restricted to acute heart failure, and possible differences in benefit by sex and by baseline iron-transport capacity emerged as hypothesis-generating candidate explanations for residual heterogeneity, warranting prospective confirmation rather than immediate clinical application. Evidence was drawn predominantly from FCM trials, with more limited supporting data for ferric derisomaltose and minimal data for other formulations; findings should not be extrapolated beyond HFrEF, as HF with preserved ejection fraction populations were not separately represented in this literature. Because the available reviews draw heavily on a shared and aging set of trials (corrected covered area of 31.9%, indicating very high primary-study overlap), this synthesis should be regarded as clarifying rather than expanding the evidence base. Taken together, IV iron repletion, particularly with FCM, in iron-deficient HFrEF reduces hospitalizations and improves quality of life, but a mortality benefit has not been established, underscoring the need for adequately powered trials designed specifically to resolve this question.”

4. 4

   Hypersensitivity to Intravenous Iron Preparations

   Children (Caimmi et al.)Published Sep 27, 2022Checked Oct 16, 2026

   “Intravenous iron is widely used for the treatment of iron deficiency anemia when adherence to oral iron replacement is poor. Acute hypersensitivity reactions during iron infusions are very rare but can be life threatening. Major risk factors for hypersensitivity reactions include a previous reaction to an iron infusion, a fast iron infusion rate, multiple drug allergies, atopic diseases, high serum tryptase levels, asthma, and urticaria. The management of iron infusions requires meticulous observation, and, in the event of an adverse reaction, prompt recognition and severity-related interventions by well-trained medical and nursing staff. Avoidance of IV iron products in patients with iron hypersensitivity reactions may not be considered as a standard practice.”

5. 5

   Hypophosphatemia in Patients Receiving Intravenous Iron Supplementation for Iron-Deficiency Anemia: A Narrative Review.

   Journal of clinical medicine (Inghilleri & Franchini)Published Jun 18, 2026Checked Oct 16, 2026

   “Persistent hypophosphatemia can cause osteomalacia due to reduced bone mineralization, leading to bone pain and pseudofractures. Ferric carboxymaltose (FCM) can impact phosphate homeostasis through an increase in fibroblast growth factor 23, leading to increased urinary phosphate excretion and hypophosphatemia. In clinical trials, rates of hypophosphatemia were significantly higher in patients receiving FCM compared with other IV iron formulations, such as ferric derisomaltose and ferumoxytol. Treatment guidelines recommend monitoring serum phosphate levels in patients receiving FCM who are at risk for low phosphate or who require repeat infusions, and alternative iron formulations should be considered in at-risk patients. This narrative review summarizes current evidence regarding IV iron-induced hypophosphatemia in individuals with IDA and examines the underlying pathophysiology and clinical evidence for IV iron-induced hypophosphatemia, particularly with FCM, the populations most at risk, and the clinical consequences of persistent hypophosphatemia.”

6. 6

   Hypophosphatemia Associated with Intravenous Iron Therapies for Iron Deficiency Anemia: A Systematic Literature Review

   Therapeutics and Clinical Risk Management (Glaspy et al.)Published Apr 1, 2020Checked Oct 16, 2026

   “The SLR yielded 511 unique publications, with 40 records meeting the final inclusion criteria. Most studies did not report phosphate monitoring methodology or an explicit definition of hypophosphatemia. Hypophosphatemia rates ranged from 0.0% to 92.1% for ferric carboxymaltose (FCM), 0.0% to 40.0% for iron sucrose, 0.4% for ferumoxytol, and 0.0% for low-molecular-weight (LMW) iron dextran. Randomized controlled studies described hypophosphatemia as "asymptomatic" or did not report on other associated sequelae. Eleven case reports detailed treatment-emergent hypophosphatemia in patients treated with FCM. Patients with acute hypophosphatemia primarily developed severe fatigue; those with repeated FCM dosing developed chronic hypophosphatemia associated with osteomalacia and bone deformities. Studies analyzed in this SLR reported a range of hypophosphatemia rates, with the highest consistently seen in patients treated with FCM. Across the clinical literature, there appeared to be minimal standardization of phosphate monitoring and definitions of hypophosphatemia.”