What supplements or treatments are recommended for an 18-year-old female with iron deficiency (low iron saturation of 13%) and symptoms of fatigue and depression?

Management of Iron Deficiency in an 18-Year-Old Female with Low Iron Saturation, Fatigue, and Depression

Oral iron supplementation with ferrous sulfate 60-65 mg elemental iron once daily is the recommended first-line treatment for this patient with iron deficiency (iron saturation 13%), fatigue, and depression. 1, 2

Diagnosis and Assessment

• The patient's iron saturation of 13% (below normal range of 15-55%) indicates iron deficiency, which is common in adolescent females and women of childbearing age 1, 3
• Iron deficiency can cause fatigue and depression, even before anemia develops 2, 4, 5
• Additional testing should include:
  • Complete blood count to assess for anemia
  • Serum ferritin (the most sensitive marker for iron stores)
  • Transferrin saturation
  • Total iron binding capacity (TIBC)
  • C-reactive protein (to assess for inflammation) 1, 3

Treatment Approach

Oral Iron Supplementation

• First-line therapy: Ferrous sulfate 200 mg once daily (providing approximately 60-65 mg elemental iron) 1, 6
• Alternate-day dosing may improve absorption and reduce side effects compared to daily dosing 1, 7
• Take on an empty stomach or with vitamin C-containing foods to enhance absorption 3
• Avoid taking with calcium, dairy products, tea, coffee, or antacids which inhibit absorption 3

Duration of Treatment

• Continue treatment for 3 months after normalization of iron levels to adequately replenish stores 3
• Expected improvement in symptoms may begin within 1-2 weeks 4, 8
• Monitor response with repeat iron studies after 4-8 weeks of treatment 3

Managing Side Effects

• Common side effects include constipation, diarrhea, and nausea 1
• If side effects occur:
  • Consider alternate-day dosing (improves tolerance while maintaining efficacy) 1, 7
  • Take with small amounts of food if needed (though this reduces absorption)
  • Consider switching to a different iron formulation if intolerance persists

Indications for Intravenous Iron

Consider IV iron if:

• Oral iron is not tolerated despite adjustments
• No improvement after 4-8 weeks of oral therapy
• Ongoing blood loss exceeds what oral supplementation can replace
• Conditions affecting absorption (e.g., inflammatory bowel disease) 1

Additional Considerations

Dietary Recommendations

• Increase consumption of iron-rich foods:
  • Heme iron sources (better absorbed): Red meat, fish, poultry
  • Non-heme iron sources: Beans, lentils, spinach, fortified cereals
• Include vitamin C-rich foods with meals to enhance iron absorption 3

Evaluation for Underlying Causes

• Assess menstrual blood loss (heavy menstruation is a common cause in young women) 1, 3
• Consider gastrointestinal causes of blood loss or malabsorption 1, 2
• Evaluate dietary intake and patterns 1

Follow-up

• Check hemoglobin within 4 weeks to assess initial response 3
• Repeat iron studies after 4-8 weeks of treatment 3
• Target ferritin level >50 μg/L in the absence of inflammation 3

Special Considerations for Depression

• Iron deficiency may contribute to depression through its role in neurotransmitter synthesis 5
• Studies show improvement in mood and fatigue with iron supplementation in iron-deficient women, even without anemia 4, 8, 5
• If depression symptoms persist despite iron repletion, consider standard depression treatments