Iron deficiency anemia happens when the body lacks the iron it needs to make hemoglobin, so red cells become small and pale. The cause is usually blood loss, low intake or poor absorption, and finding that cause matters as much as replacing iron.
Key symptoms
- Tiredness, weakness and less exercise tolerance
- Shortness of breath or palpitations on exertion
- Headache, dizziness, cold hands and feet
- Craving ice or non-food items (pica), restless legs
- Heavy periods, black stools or other blood loss
What you find on exam
- Pale skin, conjunctivae and nail beds
- Fast heart rate, soft flow murmur
- Spoon-shaped nails, cracks at the corners of the mouth, smooth tongue
- Abdominal and rectal exam for a bleeding source when indicated
Tests
- Blood count: low hemoglobin with small red cells (low MCV)
- Ferritin: low confirms iron deficiency; inflammation can make it look normal
- Iron studies: low iron and transferrin saturation, high TIBC
- Find the cause: stool tests, endoscopy in men and postmenopausal women, celiac testing
Treatment basics
- Oral iron, such as ferrous sulfate once daily or every other day
- Take it on an empty stomach with vitamin C; warn about dark stools and constipation
- IV iron if oral iron fails, is not tolerated or is poorly absorbed
- Treat the cause; recheck hemoglobin in 2 to 4 weeks
Red flags
- Chest pain, fainting or shortness of breath at rest
- Ongoing bleeding, such as black or bloody stools
- Older adult with new anemia and weight loss (possible colon cancer)
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.