How common is shortness of breath in iron deficiency anaemia?

Iron deficiency reduces the materials available to make haemoglobin, the part of red blood cells that carries oxygen. With less oxygen delivered to muscles and organs, the heart and lungs may work harder during activity. You may notice breathlessness when walking quickly, climbing stairs, or exercising, along with tiredness, reduced stamina, dizziness, headaches, or a racing heartbeat. The severity of breathlessness can vary with the degree and speed of the anaemia and with other health conditions.

Breathlessness has many possible causes, including asthma, chest infections, heart problems, anxiety, and other forms of anaemia. The symptom alone cannot identify iron deficiency anaemia. A clinician may ask about bleeding, diet, menstrual periods, digestive symptoms, medicines, and other illnesses, then arrange a blood count and iron-related tests when appropriate.

Arrange a medical assessment if breathlessness is new, persistent, or limiting normal activities. Keep a note of when it occurs, whether it is getting worse, and any associated symptoms. Tell the clinician about heavy or prolonged menstrual bleeding, black or bloody stools, recent illness, restrictive eating, pregnancy, or medicines that could contribute to bleeding. Do not start high-dose iron without advice; the right treatment depends on the test results and the reason for the deficiency. Treatment may involve iron replacement and addressing blood loss or reduced absorption.

Seek emergency help for severe or rapidly worsening breathlessness, difficulty speaking because of breathing, blue or grey lips, fainting, new confusion, or severe chest pressure or pain. Seek prompt medical care if breathlessness occurs at rest, wakes you at night, follows a significant bleed, or comes with coughing blood, a very fast or irregular heartbeat, or one-sided leg swelling. These features can signal a problem that needs urgent assessment, whether or not iron deficiency is present.

You could ask: What blood tests will check for iron deficiency and other causes of anaemia? Could blood loss or reduced iron absorption be contributing? Is my level of activity safe while this is being investigated? What treatment is suitable for me, and when should my symptoms be reviewed?