Frank syncope: what fainting can mean

A person may feel warm, nauseated, light-headed or have tunnel vision before losing consciousness, although warning symptoms are not always present. Recovery is often quick, but a fall can cause injury. Triggers can include prolonged standing, pain, emotional distress, heat or inadequate fluid intake. Other causes include dehydration, anaemia, low blood glucose or an abnormal heart rhythm such as atrial fibrillation. The event description matters: note what happened beforehand, how long awareness was lost, movements, injury, confusion afterwards and whether recovery was complete.

If someone faints, lay them flat and raise their legs when safe, loosen tight clothing and check breathing. Do not give food or drink until they are fully alert. Turn them on their side if they are vomiting or not fully awake, and call emergency services if breathing is abnormal. Once recovered, arrange medical review, especially after a first episode, repeated episodes, an injury or fainting during exertion. Until assessed, avoid driving, heights and swimming alone if another episode could put you at risk.

Call emergency services for fainting during exercise, chest pain, severe breathlessness, a racing or irregular heartbeat, a serious injury, prolonged unresponsiveness, seizure-like activity, new weakness or speech trouble. Urgent assessment is also needed when fainting occurs without warning, while lying down, or in someone with known heart disease. Do not assume a brief recovery makes these features harmless.

Ask what likely triggered the episode, whether you need an ECG or blood tests, how to recognise an impending faint, and which activities should be paused. Bring a witness account and a list of medicines, including anything that may lower blood pressure or blood glucose.