Dizziness with diarrhoea

Frequent loose stools remove water and electrolytes. This can lower circulating fluid and cause thirst, dry mouth, weakness, headache, or lightheadedness when standing. Vomiting, fever, hot weather, and reduced eating can increase the effect. Dehydration is a common explanation, but dizziness may also come from anaemia, hypoglycaemia, a balance disorder, anxiety, or a heart rhythm problem. Diarrhoea does not by itself identify the cause of dizziness. Note stool frequency, blood or mucus, abdominal pain, fever, recent travel, new medicines, and whether urine has become unusually dark or infrequent.

Rest and take frequent small sips of water or an oral rehydration drink. Eat light foods as tolerated, and avoid alcohol while recovering. Stand slowly and do not drive if you feel faint. Do not take anti-diarrhoeal medicine without advice if there is blood in the stool, significant fever, or severe abdominal pain. A clinician can assess hydration, blood pressure, medicines, glucose, and blood tests when symptoms are persistent or recurrent.

Seek urgent care for fainting, confusion, severe weakness, chest pain, severe breathlessness, severe abdominal pain, blood or black stool, or inability to keep fluids down. Get prompt medical advice for signs of dehydration, persistent diarrhoea, high fever, or diarrhoea in a person who is pregnant, elderly, or medically vulnerable.

Ask whether you need examination, electrolyte or blood tests, and a stool test. Mention recent antibiotics, travel, sick contacts, chronic bowel disease, diabetes medicines, pregnancy possibility, and the amount you have been able to drink.