Fast heart palpitations: what to know

Palpitations are the feeling of a racing, pounding, fluttering or skipped heartbeat. Triggers can include exercise, anxiety, caffeine, nicotine, some medicines, dehydration, low blood sugar, fever or an overactive thyroid. Anaemia can also make the heart beat faster as the body carries less oxygen.

Some rhythm problems, including atrial fibrillation, cause an irregular pulse. Palpitations alone do not establish a diagnosis. Details about onset, duration, regularity, triggers and other symptoms help a clinician decide whether an examination, blood tests or heart monitoring is appropriate.

Stop strenuous activity, sit or lie somewhere safe, and breathe slowly. Avoid caffeine, nicotine and recreational stimulants while symptoms continue. Note the time, pulse pattern if you can check it safely, what you were doing, and symptoms such as dizziness or chest discomfort. Do not drive if you feel faint.

Arrange a routine appointment if episodes recur, last longer than usual or occur with fatigue, breathlessness or reduced exercise tolerance. Bring a list of medicines and supplements, including recent changes.

Call emergency services for palpitations with chest pain, severe breathlessness, fainting, new confusion, severe dizziness or a new weakness. Seek prompt assessment for a very fast or irregular heartbeat that does not settle, especially if you have known heart disease or feel increasingly unwell.

Could my symptoms reflect a rhythm problem, anaemia, thyroid issue or another trigger? Should I have an ECG or blood tests? Which pulse changes matter? Are any medicines or supplements contributing? What should I do if the episode returns?