From the Guidelines
Iron supplements should be taken for at least 3 months after correction of anaemia to replenish iron stores. This recommendation is based on the guidelines for the management of iron deficiency anaemia by the British Society of Gastroenterology 1. The goal of iron supplementation is not only to correct anaemia but also to replenish body iron stores.
For patients with low ferritin levels, iron supplements should be continued until ferritin levels return to the normal range. The normal range for ferritin levels is typically 20-200 ng/mL for women and 30-300 ng/mL for men. It is essential to follow up with blood tests every 3 months to monitor progress.
Some studies suggest that post-treatment serum ferritin levels of >400 μg/L can prevent recurrence of iron deficiency within the following 1–5 years 1. However, this study is more relevant to patients with inflammatory bowel diseases, and the general recommendation for iron supplementation duration is still based on the guidelines provided by the British Society of Gastroenterology 1.
Key points to consider when taking iron supplements include:
- Take iron supplements on an empty stomach with vitamin C (like orange juice) to enhance absorption
- Avoid taking iron supplements with calcium, dairy, coffee, tea, or antacids, which can reduce absorption
- Be aware of potential side effects, such as constipation, nausea, and dark stools, and discuss them with your healthcare provider if bothersome.
From the Research
Duration of Iron Tablets for Low Ferritin
- The duration of iron tablets for low ferritin is not directly stated in the provided studies, but we can look at the duration of treatment in the studies to get an idea.
- In the study 2, patients with moderate to severe CKD and iron deficiency were treated with ferric citrate or ferrous sulfate for 12 weeks.
- In the study 3, women with iron-deficiency anemia were given iron supplements on alternate days or consecutive days for a period of 16 days, with a second period of treatment starting after a 16-day incorporation period.
- There is no direct evidence in the provided studies to suggest a specific duration for iron tablets to treat low ferritin levels.
- However, the study 3 suggests that alternate day dosing of oral iron supplements may be preferable to increase iron absorption, and the study 2 shows that treatment with ferric citrate for 12 weeks resulted in a greater increase in TSAT and ferritin concentrations in individuals with moderate to severe CKD and iron deficiency.
Treatment Duration and Iron Absorption
- The study 3 found that iron absorption from supplements is greater with alternate day than with consecutive day dosing in iron-deficient anemic women.
- The study 2 found that treatment with ferric citrate for 12 weeks resulted in a greater mean increase in TSAT and ferritin concentrations in individuals with moderate to severe CKD and iron deficiency.
- The optimal duration of treatment with iron tablets for low ferritin levels may depend on various factors, including the severity of iron deficiency, the presence of underlying medical conditions, and the individual's response to treatment 2, 3.