Underlying causes of orthostatic hypotension

A blood-pressure drop on standing can happen when there is too little circulating fluid, when blood vessels do not tighten promptly, or when the heart cannot increase output enough. Vomiting, diarrhoea, fever, heavy sweating, or bleeding may reduce fluid or blood volume. Blood-pressure medicines, water tablets, some antidepressants, and other treatments can contribute. Diabetes and disorders affecting automatic nerve control can also interfere with the body’s position response. More than one factor may be present.

Write down your symptoms, recent illness, fluid intake, alcohol use, and every prescription, over-the-counter medicine, and supplement. Do not stop a prescribed medicine on your own. A clinician may compare blood pressure and pulse in different positions, review your heart and nervous-system symptoms, and arrange tests guided by your history. Treating the contributor may improve episodes, but the right approach depends on your overall health.

Arrange an appointment for repeated episodes, new symptoms after a medicine change, or dizziness with weakness and reduced exercise tolerance. Seek urgent care for fainting with bleeding, black stools, chest pain, severe breathlessness, confusion, or a serious injury. Sudden symptoms after significant fluid loss also need prompt attention.

Ask which possible contributors fit your history, whether your medicines can be adjusted, and which tests are appropriate. Ask for a clear plan for fluids, activity, and what to do during an episode.