Treatment of Hypoferritinemia (Ferritin <15 ng/mL)
Start oral iron supplementation immediately with ferrous sulfate 200 mg three times daily, as a ferritin level below 15 ng/mL confirms absolute iron deficiency and requires treatment to replenish depleted iron stores. 1, 2
Diagnostic Confirmation
- Ferritin <15 ng/mL definitively indicates absolute iron deficiency, even in the absence of anemia 1, 2
- This threshold applies in patients without clinical or biochemical evidence of inflammation 1
- In the presence of inflammation (elevated CRP or clinical signs), the diagnostic threshold increases to 30-100 ng/mL, but your patient's ferritin is below even the strictest cutoff 1
First-Line Treatment: Oral Iron Supplementation
Ferrous sulfate 200 mg three times daily is the recommended first-line therapy due to its proven effectiveness, simplicity, and low cost 2. Alternative formulations include:
- Ferrous gluconate (equally effective) 2
- Ferrous fumarate 325 mg daily 3
- Liquid preparations if gastrointestinal side effects occur with tablets 2
Enhancing Absorption
- Add ascorbic acid (vitamin C) to enhance iron absorption, particularly if initial response is poor 2
- Take iron on an empty stomach, ideally in the morning 4
- Avoid foods and drinks that inhibit iron absorption (tea, coffee, calcium-rich foods) 4
- Administer no more than once daily to maximize absorption 4
Treatment Duration
Continue iron therapy for a full 3 months after hemoglobin normalizes to adequately replenish iron stores 2, 5. This is critical—the goal is not merely correcting anemia but fully restoring iron reserves to prevent recurrence 2.
Monitoring Response
- Hemoglobin should rise by approximately 2 g/dL after 3-4 weeks of therapy 2
- Failure to respond suggests poor compliance, continued blood loss, or malabsorption 2
- Once normalized, monitor hemoglobin and red cell indices every 3 months for 1 year, then annually 2
- Recheck ferritin in doubtful cases 2
When to Consider Intravenous Iron
Reserve parenteral iron for specific situations:
- Intolerance to at least two different oral iron preparations 2
- Non-compliance with oral therapy 2
- Malabsorption conditions (inflammatory bowel disease) 4
- Severe symptomatic anemia requiring urgent correction 4
Investigate Underlying Causes
- Heavy menstrual bleeding affects 5-10% of menstruating women and is the most common cause in premenopausal females 2
- Gastrointestinal blood loss in other populations 1
- Dietary insufficiency (vegetarian/vegan diets, eating disorders) 5, 4
- Chronic inflammatory conditions affecting iron absorption 1
Critical Pitfalls to Avoid
- Never continue daily iron supplementation once ferritin normalizes or becomes elevated—this is potentially harmful 5
- Do not stop treatment prematurely when hemoglobin normalizes; continue for 3 full months to replenish stores 2, 5
- Do not overlook the need to address underlying causes of iron loss 2
- In patients with chronic inflammatory conditions, ferritin may be falsely elevated despite true iron deficiency; check CRP to exclude acute phase reaction 1, 5