Background: In the United States (US), several intravenous (IV) iron products are available for treatment of iron deficiency, including low molecular weight iron dextran (LMWID), iron sucrose (IS), ferumoxytol (FM), ferric carboxymaltose (FCM), ferric derisomaltose (FD), and sodium ferric gluconate (FG). However, these IV iron products are associated with rare, but serious, hypersensitivity and anaphylactic reactions. Objective: This study aimed to assess the frequencies of hypersensitivity and anaphylactic reactions and associated downstream medical costs of the six IV iron products in the US. Methods: This study used data from the US Food and Drug Administration (FDA) Adverse Event Reporting System (FAERS) from January 1, 2014, to June 30, 2024. The lower bound of the 90% confidence interval of the reporting odds ratio (ROR05) was used to identify a likely drug adverse event (AE) association related to hypersensitivity and anaphylactic reactions. Downstream medical costs were estimated using Agency for Healthcare Research and Quality/Healthcare Cost and Utilization Project data. Results: Signal strength of a likely drug-AE association for hypersensitivity was highest with FG (ROR05=9.66) and lowest with FCM (2.87). Signal strength for anaphylactic reactions was highest with FM (43.59) and lowest with FCM (6.99). The medical cost per AE was lowest with FCM (US$2,348) and highest with LMWID ($9,593). Conclusion: FCM had the lowest signal strength of a likely drug AE association for hypersensitivity and anaphylaxis and the lowest medical cost per AE in the US patient population, demonstrating its potential value by improving patient safety while lowering overall medical spending.