Diarrhea, fainting and sweating

Fainting occurs when the brain briefly receives too little blood flow. Diarrhea can reduce circulating fluid, while sweating may worsen that loss. A person with diabetes may also develop Hypoglycaemia, especially when illness reduces food intake. Anaemia and Atrial Fibrillation are other conditions a clinician may consider when fainting is recurrent, occurs with palpitations or comes with breathlessness.

Lie flat, raise the legs, move away from heat and loosen tight clothing. Do not stand suddenly or drive. Once fully alert and able to swallow, take small sips of an oral rehydration drink. Follow your personal diabetes sick-day plan if relevant, have someone stay with you and arrange medical advice even after quick recovery.

Call emergency services for ongoing unconsciousness, confusion, chest pain, severe breathlessness, a seizure, injury, new weakness, irregular pounding heartbeat or inability to drink. Urgent assessment is also needed for repeated fainting, blood or black stool, very little urine, severe abdominal pain or ongoing heavy sweating. Children, older adults, pregnant people and those with heart disease or diabetes should receive advice early.

What was happening before I fainted? Could dehydration, blood sugar, anaemia or heart rhythm explain it? Do I need an ECG, blood tests or a medication review? What should I do if diarrhea returns?