What should you know about basal syncope?

Consciousness usually returns quickly when the person is lying flat. The term syncope describes the event; it does not identify the underlying trigger by itself.

A person may notice light-headedness, blurred or narrowing vision, nausea, warmth, sweating, weakness, or ringing in the ears before passing out. Some people have little warning. During a faint, the body may become limp and the skin may look pale. A short period of tiredness or confusion can follow, but prolonged confusion is not typical and needs assessment.

Common reflex triggers include prolonged standing, suddenly standing up, emotional distress, pain, seeing blood, a hot environment, or not drinking enough. Other possibilities include low blood sugar, anaemia, an abnormal heart rhythm, or medication effects. A clinician may ask what happened immediately before the episode, whether there was an injury, and how quickly normal awareness returned.

If you feel faint, lie down straight away and raise your legs if you can. If lying down is not possible, sit and lower your head between your knees. Move away from heat, loosen tight clothing, and take slow breaths. Do not try to walk until the feeling has fully settled.

If someone has fainted, lay them on their back, check that they are breathing normally, and protect them from nearby hazards. Do not give food or drink until they are fully awake. If they do not wake promptly, place them in the recovery position if they are breathing and call emergency services. Arrange medical advice after an unexplained first faint, repeated episodes, or a fall-related injury.

Call emergency services if the person is not breathing normally, does not regain consciousness promptly, has severe chest pain, trouble breathing, a sudden severe headache, new weakness, difficulty speaking, or a seizure-like episode. Urgent assessment is also needed when fainting occurs during exercise, while lying down, or with a forceful or irregular heartbeat.

Seek prompt medical advice after a head injury, significant bleeding, pregnancy, or repeated fainting. A clinician should also review fainting in someone with known heart disease or a family history of sudden unexplained death. Conditions such as anaemia, dehydration, hypoglycaemia, and atrial fibrillation can require specific treatment, so do not assume every episode is a simple reflex faint.

Ask what triggers are most plausible, whether your medicines or fluid intake could contribute, and whether you need an examination, heart tracing, or blood tests. Bring a timeline of the episode, including posture, warning symptoms, food and drink beforehand, injuries, witness observations, and the time it took to feel normal again.