Dizziness when you stand up

When you stand, gravity pulls about half a litre of blood down into your legs and abdomen. To keep enough blood reaching your brain, your body reacts within seconds: your blood vessels tighten and your heart speeds up slightly.

This is controlled by your autonomic nervous system, the "automatic" system that runs the things you never think about, like heart rate, blood pressure, and digestion.

If this adjustment is too slow, too weak, or there is not enough blood volume to start with, less blood reaches the brain for a moment. That is what you feel as dizziness.

Symptoms come on within seconds to a few minutes of standing and usually ease when you sit or lie down. They can include:

• Lightheaded, woozy, or "about to faint"
• Blurred, dim, or "tunnel" vision
• Nausea
• Feeling unsteady or weak in the legs
• Feeling shaky, sweaty, or foggy
• A dull ache across the shoulders and back of the neck (sometimes called "coat-hanger" pain)
• In more severe cases, fainting

This is different from vertigo, where the room seems to spin. Vertigo usually comes from the inner ear and has other causes. If you have spinning, especially when you turn your head or roll over in bed, let your doctor know, because it points in a different direction.

Dizziness on standing has many possible causes. Some of the most common are:

Usually harmless

• A brief head rush. Standing up quickly can cause a few seconds of dizziness, even in healthy people. It is more common in young, tall, and slim people. If it passes within about half a minute, it is usually nothing to worry about.
• Not enough fluid or food. Not drinking enough, skipping meals, or losing fluid through heat, sweating, or a stomach bug.
• Heat and hot showers. Warmth widens blood vessels, so more blood stays in the legs.
• Alcohol. It widens blood vessels and dehydrates you.

Worth checking with a doctor

• Medicines. Blood pressure medicines, water tablets (diuretics), some antidepressants, and some medicines for prostate problems or Parkinson's disease can cause dizziness when standing.
• Low iron or anaemia. Fewer red blood cells means less oxygen reaches the brain.
• Being unwell for a long time. After a long illness, time in bed, or long periods of rest, the body gets worse at adjusting to being upright.
• Orthostatic hypotension. Your blood pressure drops clearly within a few minutes of standing.
• POTS. Your blood pressure stays about the same, but your heart rate rises by at least 30 beats per minute and stays high. Read the POTS guide.
• Fainting reflex. Some people faint after standing still for a long time, in heat, or at the sight of blood. This is called vasovagal or reflex syncope.
• Thyroid problems, low blood sugar, or vitamin B12 deficiency.

Less common, but important

• Heart rhythm problems or heart valve disease. These can cause dizziness or fainting, especially during exercise.
• Nerve damage, for example from long term diabetes, which can affect the nerves that control blood pressure.

Many people notice dizziness when standing for the first time after COVID or another infection. It can come from the infection itself, from lost fluid, or from being in bed for a long time. For some, it gets better within weeks. For others it lasts, and it can be a sign of POTS or another form of dysautonomia, where the automatic system that controls heart rate and blood pressure does not work as it should.

If your dizziness has lasted for more than three months after an infection, it is worth checking your heart rate and blood pressure when you stand.

• It passes within seconds. Often a brief head rush.
• It builds up over minutes of standing, and your heart races. Could be POTS.
• It comes with a clear drop in blood pressure. Could be orthostatic hypotension.
• It started after a new medicine. Talk to the doctor who prescribed it.
• It happens during exercise, or with chest pain. Needs checking soon.

Stand test. Heart rate and blood pressure are measured after you have been lying down for a while, and then several times over 10 minutes of standing. This shows whether your blood pressure drops, your heart rate rises too much, or both. It can be done at a clinic, or at home with a blood pressure monitor and clear instructions.

What your vårdcentral can check:

• Blood pressure lying and standing
• An ECG, a recording of your heart's rhythm
• Blood tests, for example blood count, iron levels (ferritin), thyroid function, blood salts, blood sugar, and vitamin B12
• A review of your medicines

Simple everyday measures make a real difference for most people, and they are the foundation of treatment:

• Stand up in stages. Move from lying to sitting, wait a moment, then stand slowly, especially first thing in the morning and after meals.
• Drink more fluid. Aim to stay well hydrated through the day. A quick glass of water (about 500 ml) before getting up can raise standing blood pressure.
• Consider more salt, which helps the body hold on to fluid. Check with a doctor first if you have high blood pressure, or heart or kidney disease.
• Eat regularly, and choose smaller meals if big meals make you dizzy.
• Use your muscles. Cross your legs, clench your thighs and buttocks, or rise onto your toes when you feel symptoms or before you stand.
• Try compression. High-waisted compression tights or an abdominal binder reduce blood pooling in the legs and belly.
• Avoid triggers where you can: standing still for long periods, hot showers and hot rooms, large carbohydrate-heavy meals, and alcohol.
• Act on the warning signs. Sit or lie down as soon as you feel dizzy, before you faint.
• Keep a short diary. Note when it happens, what you were doing, and your heart rate if you can measure it. This helps your doctor a lot.

If everyday measures are not enough, a doctor may consider medicines that raise or steady standing blood pressure. The goal of treatment is to relieve your symptoms and prevent falls, not to hit a particular blood pressure number.

Call or go to the emergency department if you have:

• Fainting, especially during exertion or if it causes injury
• Chest pain or pressure
• A very fast or irregular heartbeat that does not settle when you lie down
• Sudden weakness, numbness, trouble speaking, or a severe headache
• Severe shortness of breath

Contact your clinic if:

• Dizziness on standing is new, frequent, or getting worse
• You have fainted for the first time
• You are dizzy and also feel your heart racing when upright
• It started after a new medicine
• A family member has died suddenly at a young age or has a known heart rhythm problem