What should you know about transient syncope?

People often recover quickly after lying down, but the episode can still point to a trigger that needs attention. A fall during a blackout can also cause injury.

Syncope means a temporary loss of consciousness and posture. It can be preceded by light-headedness, nausea, sweating, blurred vision, ringing in the ears or a feeling of warmth. Some people have little warning.

Standing still for a long time, getting up quickly, pain, emotional distress, a hot environment or not drinking enough can contribute. Dehydration, low blood sugar and anaemia are examples of health issues that may be considered. Heart rhythm problems, including atrial fibrillation, also need consideration in the right clinical setting.

If you feel faint, sit or lie down immediately and raise your legs if this is comfortable. Loosen tight clothing and move away from heat or crowding. Do not drive, climb, swim or use machinery while you still feel unwell.

After you have recovered, arrange a medical assessment, especially if this is the first episode. Write down what you were doing beforehand, any warning symptoms, how long recovery seemed to take, medicines or substances used, and whether anyone saw movements, injury or confusion. This account helps the clinician distinguish syncope from other causes of collapse.

Seek emergency help if fainting occurs with chest pain, breathlessness, a pounding or irregular heartbeat, severe headache, new weakness, trouble speaking, ongoing confusion, significant injury or pregnancy. Urgent assessment is also appropriate if the person does not wake promptly, has repeated episodes close together, or faints during exercise or while lying down.

A collapse in an older person, someone with known heart disease, or someone taking medicines that affect blood pressure or blood sugar deserves prompt clinical advice even after apparent recovery.

Ask what the likely triggers are in your situation, whether your medicines could contribute, and whether you need tests such as an examination, blood tests or a heart rhythm check. Also ask when you can safely return to driving, sport and work duties, and what warning signs should change your plan.