As one of the commonly used oral iron supplements in clinical practice, ferrous fumarate exhibits significant differences from other iron agents (such as ferrous sulfate, ferrous succinate, and iron dextran) in terms of absorption efficiency, adverse reactions, and applicable scenarios when treating iron-deficiency anemia. A comparison of its clinical effects can be elaborated from the following aspects:
In terms of absorption and utilization, ferrous fumarate has a high iron content (approximately 33%) and exists in the form of divalent iron, which can be directly absorbed by the intestines without further reduction by gastric acid. Its bioavailability is superior to that of iron agents mainly composed of trivalent iron (such as iron dextran). Compared with traditional ferrous sulfate, ferrous fumarate is less affected by food; even when taken after meals, the decrease in absorption efficiency is smaller, which is more friendly to patients who need to take medicine with meals to reduce gastrointestinal irritation. Clinical data show that at the same dose, ferrous fumarate increases hemoglobin levels slightly faster than ferrous sulfate, making it particularly suitable for the rapid iron supplementation needs of patients with moderate iron-deficiency anemia.
In terms of adverse reactions, common side effects of iron agents include gastrointestinal irritation (such as nausea, vomiting, diarrhea, and constipation), which is related to the direct stimulation of the gastrointestinal mucosa by iron ions. Ferrous fumarate has better gastrointestinal tolerance than ferrous sulfate: ferrous sulfate releases iron ions quickly, which easily causes gastrointestinal motility disorders, while the sustained-release property of ferrous fumarate can reduce the concentration of free iron ions in the gastrointestinal tract, thereby lowering the incidence of nausea and vomiting. However, compared with ferrous succinate, ferrous fumarate may have a slightly higher incidence of constipation, which is related to individual differences in intestinal metabolism of different iron agents.
From the perspective of applicable populations, ferrous fumarate has a wide range of applications: for children with iron-deficiency anemia, its tablet or suspension dosage form is convenient for dose adjustment, and its high absorption efficiency can quickly correct anemia; for groups with high iron demand such as pregnant and lactating women, the high iron content of ferrous fumarate can reduce the number of daily administrations (usually 2-3 times a day), improving patient compliance; for elderly patients with weak gastrointestinal function, compared with ferrous sulfate, the low irritation of ferrous fumarate is more suitable for long-term use. In addition, ferrous fumarate can be used as an alternative for patients who are allergic or intolerant to ferrous sulfate.
In terms of the durability of clinical efficacy, ferrous fumarate shows stable performance in supplementing stored iron (such as serum ferritin). Studies have shown that after 8-12 weeks of continuous administration of ferrous fumarate, the recovery rate of hemoglobin levels and serum ferritin concentration in patients is comparable to that of ferrous succinate, but better than that of iron dextran (the latter has low efficiency in supplementing stored iron because the absorption of trivalent iron depends on the reduction process). This means that ferrous fumarate can more effectively prevent the recurrence of iron-deficiency anemia during the maintenance treatment stage after anemia correction.
It should be noted that the clinical effect of ferrous fumarate is also affected by individual differences in patients. For example, gastrointestinal pH, concurrent use of antacids, or consumption of tannic acid-containing foods (such as tea and coffee) may reduce its absorption efficiency. Therefore, in clinical application, it is necessary to adjust the medication plan according to the specific situation of the patient to maximize its iron supplementation effect.
Ferrous fumarate has significant advantages in the clinical treatment of iron-deficiency anemia due to its high bioavailability, low gastrointestinal irritation, and wide range of applicable populations. It is a better choice especially in scenarios where rapid iron supplementation is needed or patients have poor tolerance to traditional iron agents.
