What should you know about frequent fainting causes?

Fainting, also called syncope, happens when the brain briefly receives too little blood flow. Standing suddenly, prolonged standing, heat, pain, fear, dehydration, or not eating can contribute. Dehydration reduces circulating fluid, while hypoglycaemia means blood sugar is too low. Anaemia can reduce oxygen delivery. Atrial fibrillation and other rhythm disturbances may affect how efficiently the heart pumps. These possibilities cannot be separated safely from symptoms alone.

If warning symptoms such as warmth, nausea, sweating, or dimming vision appear, lie flat and raise your legs if safe. If someone has fainted, protect them from injury, check breathing, and place them on their side if they are breathing but not fully alert. Do not give food or drink until they are awake and able to swallow. Arrange a clinical assessment and record posture, activity, food and fluid intake, warning symptoms, duration, injury, and recovery.

Call emergency services for fainting during exercise, chest pain, breathlessness, a racing or irregular heartbeat, seizure-like movements, serious injury, prolonged confusion, or failure to wake normally. Urgent assessment is also needed when fainting occurs without warning, while lying down, or in someone with known heart disease. Do not drive until a clinician has advised you.

Ask whether your medicines, hydration, blood sugar, blood count, blood pressure, or heart rhythm need checking. Share any family history of sudden heart problems and describe what happened immediately before and after each spell. Ask what activity restrictions are sensible while the cause is being investigated.