How common is palpitations in dehydration?

Fluid loss may also disturb the balance of salts needed for normal muscle and heart activity. Heat exposure, strenuous exercise, fever and some medicines can increase the risk. Palpitations can have other causes too, including an abnormal rhythm, so improvement after drinking does not prove dehydration was the only explanation.

A clinician may ask about recent fluid loss, urine output, medicines and health conditions. They may check your pulse, blood pressure and hydration, with tests when symptoms are significant or do not settle.

Rest somewhere cool and take frequent small sips of water. After substantial sweating or gastrointestinal fluid loss, a clinician or pharmacist can advise whether an oral rehydration drink is suitable. Avoid alcohol while recovering, and do not rapidly drink large amounts if you have been vomiting. Seek advice if you cannot keep fluids down or urine becomes very scant.

Get emergency help for palpitations with fainting, chest pain, severe breathlessness, confusion, seizure or extreme weakness. Urgent assessment is needed if you are unable to drink, have ongoing vomiting or diarrhoea, or remain dizzy when standing despite attempts to replace fluids. Babies, older adults and people with serious medical conditions may need help sooner.

Ask what may have caused the fluid loss, which drink is appropriate, whether medicines need review, and what signs should prompt same-day or emergency care.