What should you know about fainting a lot?

Fainting a lot needs medical assessment because repeated blackouts can have several causes, including heart rhythm problems, dehydration, low blood sugar, or anaemia. Fainting, also called syncope, happens when the brain briefly receives too little blood flow. A clinician may need to review what happened before each episode, your medicines, and your heart and general health.

A blackout may follow standing for a long time, heat, pain, fear, illness, or a sudden drop in blood pressure. It can also occur with dehydration or hypoglycaemia, especially when meals or fluids have been missed. Anaemia can reduce the blood's oxygen-carrying capacity and contribute to light-headedness or fainting. A heart rhythm problem, including atrial fibrillation, is another possibility that deserves assessment. Keep a record of warning symptoms, posture, food and drink, activity, injuries, and how quickly you recovered.

Lie down promptly and raise your legs if you can. If lying down is not possible, sit and lower your head between your knees. Loosen tight clothing, move away from heat, and avoid standing suddenly. Do not drive, climb, swim alone, or use machinery until a clinician has assessed recurrent episodes. If someone has fainted, check that they are breathing normally, protect them from injury, and place them on their side if they are breathing but remain unresponsive. Do not give food or drink until they are fully awake.

Seek emergency help if fainting happens during exercise or while lying down, follows chest pain or severe breathlessness, comes with a racing or irregular heartbeat, causes a serious injury, or is followed by confusion, weakness, trouble speaking, or a seizure. Get urgent help if the person does not wake promptly, is not breathing normally, or has heavy bleeding. Even when recovery is quick, arrange a medical appointment for repeated fainting, particularly if episodes are becoming more frequent or there is a personal or family history of heart disease or sudden death.

Ask what causes should be checked in your situation, whether your medicines or fluid intake could contribute, and whether you need an electrocardiogram or blood tests. Tell the clinician about warning signs, injuries, palpitations, family heart history, and any episode witnessed by another person. Ask what activities are safe while the cause is being investigated and what symptoms should prompt emergency help.