Acute syncope: responding to a fainting episode

A person often becomes limp, falls, and then recovers without assistance. Heat, pain, emotional distress, standing still, dehydration, low blood sugar, blood loss, medicines, or a heart rhythm problem can contribute. A blackout should not be labelled as a simple faint until dangerous features have been considered.

The brain depends on steady circulation. A sudden drop in blood pressure or an abrupt change in heart rate can interrupt that supply briefly. Warning sensations may include warmth, nausea, sweating, dimming vision, ringing in the ears, or light-headedness, but cardiac syncope can occur with little warning.

The setting offers useful clues: standing after illness may suggest fluid loss, while collapse during exertion or alongside palpitations raises concern about the heart. Witness details about breathing, skin colour, movements, injury, and recovery help distinguish syncope from a seizure or another cause of unconsciousness.

Ease the person onto the floor, protect the head, and check breathing. If breathing normally and no serious injury is suspected, lay them flat and raise their legs. Loosen tight clothing, provide fresh air, and remain nearby as they recover. Do not give food or drink until they are fully alert.

If the person is unresponsive but breathing, place them in the recovery position unless an injury prevents movement. If they are not breathing normally, call emergency services, begin cardiopulmonary resuscitation, and use an automated defibrillator if one is available. After recovery, they should rise slowly and avoid driving until the cause and safety implications are clear.

Call emergency services if the person does not promptly wake, has chest pain, severe breathlessness, a pounding or irregular heartbeat, new weakness or speech trouble, major bleeding, a serious injury, or ongoing confusion. Collapse during exercise, while lying down, or during pregnancy also needs urgent evaluation.

Medical review is advisable after a first unexplained faint, repeated episodes, or a blackout in someone with known heart disease. Assessment may include blood pressure lying and standing, a heart tracing, medication review, and targeted blood tests based on the history.

Describe the activity and posture before the collapse, any warning symptoms, how quickly consciousness returned, and what a witness observed. Ask whether medicines, dehydration, anaemia, glucose disturbance, or heart rhythm need checking, and whether temporary restrictions on driving, work, or exercise apply.