From the Guidelines
Ferrous sulfate should be prescribed at a dose of 200 mg (65 mg elemental iron) taken orally once daily for adults with iron deficiency anemia, as this dose has been shown to be effective in raising hemoglobin levels while minimizing gastrointestinal side effects 1.
Key Considerations
- The optimal dose and frequency of ferrous sulfate may vary depending on individual patient factors, such as the severity of iron deficiency anemia and the presence of gastrointestinal side effects.
- A once daily dose of 50-100 mg of elemental iron may be the best compromise option for initial treatment, as it balances efficacy with tolerability 1.
- Intermittent oral iron, defined as less frequently than daily, has been reported to be at least as effective as daily dosing in raising hemoglobin levels in certain populations, such as young women and pregnant women, although it may be less effective in boosting iron stores in the short-term 1.
Monitoring and Treatment Duration
- Regular monitoring of hemoglobin levels is recommended to ensure an ultimately satisfactory response, with the optimal interval being every 4 weeks until the hemoglobin is in the normal range 1.
- Treatment with ferrous sulfate should be continued for at least 2-3 months after hemoglobin levels normalize to replenish iron stores, although the exact duration required is unclear 1.
Administration and Absorption
- Ferrous sulfate should be taken on an empty stomach, ideally 1 hour before or 2 hours after meals, to maximize absorption.
- If gastrointestinal side effects occur, the medication can be taken with food, although this may reduce absorption by 40-50%.
- Vitamin C, such as orange juice, can enhance iron absorption if taken simultaneously.
From the Research
Ferrous Sulfate Dose and Frequency
- The optimal dose and frequency of ferrous sulfate supplementation can vary depending on the individual and the specific condition being treated 2, 3.
- A study published in 2020 suggests that morning doses of 60-120 mg iron as a ferrous salt given with ascorbic acid on alternate days may be an optimal oral dosing regimen for women with iron-deficiency and mild IDA 2.
- Another study published in 2017 found that once daily, low-dose ferrous sulfate (3 mg/kg of elemental iron) was effective in increasing hemoglobin concentration in infants and children with nutritional iron-deficiency anemia 3.
- The frequency of ferrous sulfate supplementation can also impact its effectiveness, with some studies suggesting that alternate-day schedules may be more effective than daily schedules in maximizing fractional iron absorption 2.
- It is worth noting that the other studies provided do not appear to be relevant to the topic of ferrous sulfate dose and frequency, as they discuss topics such as knee prostheses 4 and neuronal circuits 5.