Heart races when I stand up: what should you know?

Standing moves blood toward the legs. Your nervous system normally tightens blood vessels and adjusts the heartbeat to keep blood flowing to the brain. A brief increase can happen when you rise quickly, have not had enough fluids, or are recovering from illness. Light-headedness, blurred vision, weakness, or shakiness may occur alongside the palpitations.

Recurring episodes can have several explanations, including dehydration, anaemia or iron deficiency, low blood sugar, an overactive thyroid, anxiety, or an irregular rhythm such as atrial fibrillation. A racing heartbeat is a presentation of these conditions in some people; it does not identify the cause by itself. Heart failure can also cause breathlessness, swelling, and reduced exercise tolerance, so those symptoms should be mentioned.

Pause at the edge of the bed or chair before standing, then rise slowly while holding a stable surface. Sit or lie down if symptoms begin. Drink fluids regularly unless a clinician has told you to restrict them, and avoid driving while dizzy. Record when episodes occur, how long they last, your position, recent illness, food and drink, medicines, and any measured pulse. Arrange a clinical review if the pattern is new, frequent, worsening, or affecting daily activities.

Call emergency services for chest pain, severe breathlessness, fainting, new confusion, or a racing heartbeat that does not settle with rest. Seek prompt medical advice after an episode of collapse, or if palpitations come with marked weakness or a new irregular rhythm. Pregnancy, known heart disease, and medicines that affect blood pressure or rhythm are reasons to arrange assessment sooner.

Ask whether you need a lying-and-standing pulse and blood-pressure check, an electrocardiogram, or blood tests for anaemia, thyroid problems, and glucose. Mention whether symptoms improve when you sit down and whether your heartbeat feels regular or uneven.