What does dizziness feel like with low blood pressure?

When blood pressure falls, the brain may briefly receive less blood flow, particularly when you rise from sitting or lying down. Your vision may dim or blur, your legs may feel weak, and you may need to hold onto something. Some people notice tiredness, nausea, a cold sweat or a rapid heartbeat. Dehydration, illness, heat, blood loss and some medicines can contribute.

Low blood pressure can be harmless for some people, but repeated symptoms, falls or fainting need assessment. Dizziness is not specific to one cause, so a clinician may review medicines, hydration, heart symptoms and blood pressure in different positions.

Sit or lie down immediately and raise your legs if comfortable. Wait until the feeling passes before standing, then rise in stages and hold a stable surface. Drink fluids if you have not been told to restrict them, and avoid driving while lightheaded. Do not change prescribed blood-pressure medicine without speaking with the prescriber.

Get emergency help for fainting with chest pain, severe breathlessness, a new irregular heartbeat, confusion, one-sided weakness, trouble speaking, or a serious injury. Prompt medical review is needed for repeated fainting, ongoing vomiting, signs of bleeding, or dizziness that is sudden or worsening.

Ask whether your medicines, hydration, heart rhythm or another condition could be lowering pressure, how to measure it safely, and which symptoms should trigger urgent help.