What is the appropriate treatment for an adult patient with a ferritin level of 17, indicating depleted iron stores and iron deficiency anemia?

Treatment for Ferritin Level of 17

A ferritin of 17 ng/mL indicates depleted iron stores requiring immediate oral iron supplementation with ferrous sulfate 200 mg three times daily, continued for three months after hemoglobin normalization to fully replenish body stores. 1

Diagnostic Confirmation

Your ferritin level of 17 ng/mL confirms iron deficiency, as values below 30 ng/mL indicate depleted iron stores in otherwise healthy adults 2. The CDC guidelines specify that ferritin ≤15 ng/mL confirms iron deficiency with 98% specificity in women of childbearing age 1. At 17 ng/mL, you fall just above this threshold but clearly within the deficient range requiring treatment.

First-Line Treatment: Oral Iron Supplementation

Start ferrous sulfate 200 mg three times daily immediately 1. This is the most cost-effective and appropriate first-line therapy for uncomplicated iron deficiency 1. Alternative formulations include ferrous gluconate or ferrous fumarate, which are equally effective if ferrous sulfate is not tolerated 1.

Optimizing Oral Iron Absorption

• Take iron with vitamin C (ascorbic acid) to enhance absorption, particularly if response is poor 1
• Avoid tea and coffee around meal times as they impair iron absorption 1
• Consider alternate-day dosing (rather than daily) if gastrointestinal side effects occur, as recent data suggest better absorption and fewer adverse effects with this approach 1, 3

Expected Response Timeline

• Hemoglobin should rise by 2 g/dL after 3-4 weeks 1
• Recheck hemoglobin and ferritin at 8-10 weeks to assess treatment response 1, 4
• Continue iron for 3 months after hemoglobin normalizes to fully replenish iron stores 1

When Intravenous Iron Is Indicated

Intravenous iron should be reserved for specific situations 1, 2:

• Intolerance to at least two oral iron preparations 1
• Malabsorption conditions (celiac disease, post-bariatric surgery) 2
• Ongoing blood loss 2
• Chronic inflammatory conditions (IBD, CKD, heart failure) 2, 3
• Second or third trimester of pregnancy 2

Parenteral iron is painful, expensive, and carries risk of anaphylactic reactions, with no faster hemoglobin rise than oral preparations in uncomplicated cases 1.

Identifying and Treating the Underlying Cause

The British Society of Gastroenterology emphasizes that treatment of the underlying cause is essential to prevent further iron loss 1. Common causes to investigate include:

• Menstrual blood loss (affects 5-10% of menstruating women) 1
• Gastrointestinal bleeding (responsible for 94% of cases in men and postmenopausal women) 3
• Dietary deficiency (vegetarian/vegan diets, inadequate intake) 4, 2
• NSAID use 1, 2
• Malabsorption (celiac disease, atrophic gastritis) 2, 3

Investigation Strategy by Patient Population

For premenopausal women with heavy menstrual bleeding: Treat the bleeding source and provide iron supplementation without extensive GI investigation initially 1

For men and postmenopausal women: Bidirectional endoscopy (upper and lower GI) should be performed to identify bleeding sources 3. Testing for Helicobacter pylori and celiac disease is recommended as both commonly cause iron deficiency 3.

Monitoring and Follow-Up

• Reassess at 2-4 weeks to confirm hemoglobin response 3
• Repeat complete iron studies at 8-10 weeks (not earlier, as ferritin is falsely elevated immediately after iron administration) 1, 4
• Monitor hemoglobin and MCV every 3 months for one year, then annually 1
• Resume oral iron if hemoglobin or MCV falls below normal during follow-up 1

Common Pitfalls to Avoid

Failure to respond to oral iron is usually due to 1:

• Poor compliance (gastrointestinal side effects affect ~50% of patients) 3
• Continued blood loss
• Misdiagnosis
• Malabsorption

Do not use standard oral iron dosing to assess ferritin response early: Standard-dose ferrous sulfate (200 mg three times daily) does not cause ferritin elevation until hemoglobin normalizes 5. Only higher doses cause temporary ferritin rises within days 5.

Avoid long-term iron supplementation with normal ferritin: Once stores are replenished, continued iron administration is inefficient, causes side effects, and may be harmful 4.