From the Guidelines
For a patient with a ferritin of 39 and serum iron of 46, I recommend oral iron supplementation with ferrous sulfate 200 mg twice daily, as this is the most effective and cheapest way to correct anaemia and replenish body stores, according to the most recent guidelines 1. The patient's lab values indicate iron deficiency, with ferritin below the typical threshold of 50 ng/mL and low serum iron (normal range typically 60-170 μg/dL).
- Key points to consider when prescribing oral iron supplementation include:
- Take on an empty stomach with vitamin C (such as orange juice or a 500 mg vitamin C supplement) to enhance absorption, and separate from calcium, dairy, coffee, tea, and antacids by at least 2 hours.
- Continue supplementation for 3-6 months, even after symptoms improve, to fully replenish iron stores.
- Alternative options include ferrous gluconate or ferrous fumarate if sulfate causes intolerable gastrointestinal side effects like constipation or nausea.
- Monitor response with repeat ferritin and hemoglobin levels after 4-8 weeks of therapy. If oral supplementation fails or is not tolerated, intravenous iron formulations like iron sucrose or ferric carboxymaltose may be considered, as recommended by recent guidelines 1. Addressing the underlying cause of iron deficiency, such as blood loss or malabsorption, is also essential for successful treatment. Intravenous iron should be used if the patient does not tolerate oral iron, ferritin levels do not improve with a trial of oral iron, or the patient has a condition in which oral iron is not likely to be absorbed, as stated in the most recent expert review 1.
From the FDA Drug Label
Each tablet contains 324 mg of ferrous gluconate, equivalent to 38 mg of elemental iron, providing 211% of the U.S. recommended daily intake (RDI) of iron for adults and children 4 and older. Adult Serving Size: 1 tablet three to four times daily.
To replete a patient with a ferritin of 39 and a serum iron of 46, the patient can take 1 tablet of ferrous gluconate (containing 38 mg of elemental iron) three to four times daily 2.
- The patient's ferritin and serum iron levels indicate iron deficiency, and supplementation is necessary.
- Ferrous gluconate is an appropriate choice for repletion.
- The patient should be advised not to crush or chew tablets.
From the Research
Repletion of Iron
To replete iron in a patient with a ferritin level of 39 and a serum iron level of 46, the following options can be considered:
- Oral iron supplementation is a common and effective method for increasing hemoglobin levels and restoring iron stores 3.
- Ferrous sulfate is a widely used iron supplement, but it can cause gastrointestinal side effects 4.
- Lactoferrin supplementation has been shown to have better effects on serum iron and ferritin levels compared to ferrous sulfate, with fewer side effects 4.
- Alternate-day dosing of oral iron supplements may be preferable to consecutive-day dosing, as it can increase fractional iron absorption 5.
- The dose and frequency of iron supplementation should be tailored to the individual patient's needs, with monitoring of serum ferritin and iron levels to assess response to treatment.
Iron Supplementation Options
Some possible iron supplementation options include:
- Ferrous sulfate: 300-600 mg per day, given in divided doses 6.
- Lactoferrin: dosage varies, but has been shown to be effective in improving serum iron and ferritin levels 4.
- Alternate-day dosing: giving twice the daily target dose on alternate days, to provide the same total amount of iron 5.
Monitoring and Adjustment
It is essential to monitor the patient's response to iron supplementation, including:
- Serum ferritin levels: to assess replenishment of iron stores 6.
- Serum iron levels: to assess improvement in iron deficiency 4.
- Hemoglobin levels: to assess improvement in anemia.
- Adjustment of the dose and frequency of iron supplementation may be necessary based on the patient's response to treatment.