Why does anaemia cause palpitations?

This can feel like racing, pounding, fluttering or skipped beats, particularly during activity or when standing up quickly.

Red blood cells use haemoglobin to carry oxygen from the lungs to the body. With anaemia, there may be fewer red blood cells or less haemoglobin available, so tissues receive less oxygen with each heartbeat.

The body can respond by increasing heart rate and the force of contraction. That extra effort can make the normal rhythm easier to feel. Palpitations are a common presentation of anaemia, but they also have many other possible causes.

Arrange a clinical assessment if palpitations are new, recurrent or affecting daily activities. A clinician may ask about bleeding, diet, medicines, heavy menstrual bleeding, pregnancy, bowel symptoms and family history, then arrange a blood test to check for anaemia and help identify its cause.

Avoid starting iron supplements solely on the basis of symptoms. Iron is helpful for some causes of anaemia, while other causes need a different treatment. Until you are assessed, pace exertion, stay hydrated and note triggers, duration and any associated dizziness or breathlessness.

Seek urgent medical care for palpitations with chest pain, fainting, severe shortness of breath, confusion, marked weakness, or a sustained very fast or irregular heartbeat. These symptoms need prompt assessment regardless of whether anaemia is known or suspected.

Contact a clinician promptly if you notice black stools, vomiting blood, unusually heavy bleeding, or palpitations that are becoming more frequent, because blood loss can contribute to anaemia.

Ask what type of anaemia, if present, is suspected; whether blood loss, iron levels, vitamin levels or another cause should be checked; and whether an ECG is appropriate for the palpitations. Also ask which symptoms should prompt urgent review while treatment is underway.