--- title: Orthostatic hypotension description: What orthostatic hypotension is, why blood pressure falls and dizziness appears on standing up, why it matters for older people, how it is found and treated, and when to call an ambulance. type: disease aliases: - postural hypotension - OH - low blood pressure on standing - dizziness on standing sources: - tier: guideline org: esc title: Рекомендации ЕОК по диагностике и лечению синкопальных состояний 2018 year: 2019 doi: 10.15829/1560-4071-2019-7-130-194 url: https://doi.org/10.15829/1560-4071-2019-7-130-194 - tier: guideline org: minzdrav-rf title: Артериальная гипертензия у взрослых year: 2024 doi: 10.15829/1560-4071-2024-6117 url: https://cr.minzdrav.gov.ru/view-cr/62_3 - tier: guideline org: nice title: 'Hypertension in adults: diagnosis and management (NG136)' year: 2026 url: https://www.nice.org.uk/guidance/ng136 - tier: guideline org: nice title: Transient loss of consciousness ('blackouts') in over 16s (CG109) year: 2023 url: https://www.nice.org.uk/guidance/cg109 - tier: reference org: msd-manuals title: Orthostatic Hypotension year: 2024 url: https://www.msdmanuals.com/professional/cardiovascular-disorders/symptoms-of-cardiovascular-disorders/orthostatic-hypotension - tier: reference org: msd-manuals title: Dizziness or Light-Headedness When Standing Up year: 2024 url: https://www.msdmanuals.com/home/heart-and-blood-vessel-disorders/symptoms-of-heart-and-blood-vessel-disorders/dizziness-or-light-headedness-when-standing-up sources_checked: 2026-10-13 review: null --- Orthostatic hypotension (OH) is an excessive fall in blood pressure when a person stands up or sits up. It is not a disease in itself but a sign that blood pressure regulation is impaired, and various conditions can cause it. It is especially common in older people. It can lead to falls and fainting.

A person stands up. Gravity shifts some blood into the veins of the legs and abdomen, less blood returns to the heart for a short time, and blood pressure dips briefly. Pressure sensors in the aortic arch and the carotid arteries trigger a reflex: the heart rate rises and the blood vessels narrow, so blood pressure returns to normal before any symptoms appear.

In OH this reflex falls short. For example, when the autonomic nervous system is damaged, the blood vessels do not narrow enough on standing. More blood stays in the leg veins. Something similar happens when there is too little blood in the vessels (dehydration, blood loss) or when medicines lower blood pressure. Blood pressure falls too far, less blood reaches the brain, and light-headedness and dizziness appear; they pass quickly on lying down.

## Why it happens The most common cause of OH is medicines. It can be caused by medicines for high blood pressure and angina (including diuretics and vasodilators), some antidepressants and antipsychotics, sedatives and sleeping medicines, and alcohol. Another common cause is too little blood in the vessels: from dehydration, bleeding, diarrhoea or vomiting. OH can also appear after prolonged bed rest. In older people the pressure sensors respond less well and the arteries become less elastic, so OH is more common in them. Paradoxically, high blood pressure itself can weaken these sensors. How the treatment of high blood pressure relates to OH is covered below and in the article on [hypertension](../hypertension/). Another cause is damage to the autonomic nervous system, which controls the blood vessels without conscious effort. This happens in Parkinson's disease and other diseases of the nervous system, and also in diabetes, [amyloidosis](../cardiac-amyloidosis/) and kidney failure. Sometimes the cause is that the heart pumps less well. Symptoms get worse after exercise, after a meal (especially a heavy one), after lying down for a long time, after alcohol and with dehydration. In the ESC classification, OH may be drug-induced (the most common cause: vasodilators, diuretics, phenothiazines, antidepressants), due to volume depletion (haemorrhage, diarrhoea, vomiting), or neurogenic. Neurogenic OH is caused by primary autonomic failure (pure autonomic failure, multiple system atrophy, Parkinson's disease, dementia with Lewy bodies) or secondary autonomic failure (diabetes, amyloidosis, spinal cord injuries, autoimmune and paraneoplastic autonomic neuropathy, kidney failure). In autonomic failure the sympathetically mediated vasoconstrictor response to upright posture is insufficient. ## Symptoms Typical symptoms are faintness, dizziness, muddled thinking and blurred vision. They come on within seconds to a few minutes of standing and pass quickly on lying down. They are more likely in the morning, and are milder or absent when sitting. Exercise, a heavy meal or heat can make them worse. MSD notes that many falls may result from unrecognised OH. If an older person has fallen for no obvious reason (did not slip or trip), they may have fainted and simply not remember losing consciousness. Before a [vasovagal faint](../vasovagal-syncope/) people often sweat, feel warm or feel sick. In OH this "autonomic reaction" is usually absent. The ESC considers OH highly likely when syncope and presyncope occur when standing, are absent when lying and are milder or absent when sitting; tend to occur in the morning; are relieved by sitting or lying down; are worse straight after exertion, after meals or in a hot environment; and there is no autonomic activation. Syncope due to OH is also suggested by a temporal relationship with starting or changing the dose of vasodepressive drugs or diuretics. According to the ESC, OH is associated with a twofold higher risk of death, which is explained by the severity of comorbidities. ## How it is diagnosed The main test is measuring blood pressure and heart rate first lying down and then standing, several times over a few minutes. If the person finds it hard to stand, they may be assessed sitting up. The numbers used for the diagnosis are worded slightly differently in different guidelines, and a doctor interprets them. Once OH is confirmed, the doctor looks for its cause. They ask about medicines and other symptoms, such as constipation, problems with passing urine or with erections, problems with vision, and poor tolerance of heat. An [ECG](../../diagnostic/ecg/) and simple blood tests are usually done. If the doctor suspects a medicine, they may ask the person to stop it for a while and see whether the symptoms go away. Do not stop medicines on your own. If blood pressure does not fall on standing but the heart rate rises markedly and symptoms appear, the doctor will think of [postural orthostatic tachycardia syndrome](../postural-orthostatic-tachycardia-syndrome/). Sometimes a tilt test (described in the article on [vasovagal syncope](../vasovagal-syncope/)) or 24-hour blood pressure monitoring is needed. If there are symptoms but the measurements do not confirm OH, or the symptoms persist despite dealing with likely causes, NICE advises referral, or considering referral, to a specialist. The thresholds are worded differently; these are criteria for the clinician, not for self-testing: - ESC (I, C): syncope due to OH is confirmed when spontaneous symptoms are reproduced on standing and systolic BP falls by 20 mm Hg or more or diastolic BP by 10 mm Hg or more from baseline, or systolic BP falls below 90 mm Hg. The last condition makes this definition differ from the 2011 consensus. An isolated fall in diastolic BP is very rare, and its significance for diagnosis is unclear. - Russian Ministry of Health guideline: a fall in systolic BP of 20 mm Hg or more and in diastolic BP of 10 mm Hg or more within 3 minutes of standing up (measured at minutes 1 and 3). - NICE: a fall in systolic BP of 20 mm Hg or more, or in diastolic BP of 10 mm Hg or more, after the person has been standing for at least 1 minute. MSD: systolic BP drops by 20 mm Hg or more or diastolic BP by 10 mm Hg or more within 3 minutes of standing. In neurogenic OH the orthostatic rise in heart rate is usually small or absent, whereas in anaemia or hypovolaemia it is marked. A tilt test should be considered when OH is suspected (IIa, B), particularly to reproduce delayed OH. ABPM is recommended to detect nocturnal hypertension in patients with autonomic failure (I, B): in these patients OH is often combined with an insufficient nocturnal fall in BP. In OH due to autonomic failure the ESC advises considering a neurological assessment. ## How it is treated Treatment starts with an explanation: what is happening and how to avoid the situations that bring on symptoms. Together with lifestyle changes this can noticeably reduce symptoms. If the cause is known, it is treated; some causes cannot be cured, and then measures that ease the symptoms matter. If a medicine is causing OH, the doctor may change the treatment or stop the medicine. Only the doctor decides this: do not change or stop medicines on your own. What is usually advised: - get up slowly and carefully, especially after meals; - drink enough fluid and limit or avoid alcohol; - eat smaller meals with less carbohydrate; - be physically active regularly when possible; older people should avoid standing for long; - at the first signs of light-headedness, sit or lie down; if that is not possible, use physical manoeuvres that support blood pressure, such as squatting; - wear compression stockings or an abdominal binder, so that less blood pools in the legs and abdomen; - sleep with the head of the bed raised. More salt can help, but it may be unsuitable for people with heart disease or high blood pressure, so the doctor decides how much salt and fluid is right. If these measures are not enough, the doctor may prescribe medicines: some narrow the blood vessels, others help the body retain salt and water. According to the ESC, the vessel-narrowing medicine does not help everyone and does not cure OH. ESC (figure 12): for all patients, explanation of the diagnosis, the risks and how to avoid triggers, and adequate hydration and salt intake (I; the ESC advises adequate salt and water intake in the absence of hypertension); modification or withdrawal of drugs that lower blood pressure, physical counter-pressure manoeuvres, an abdominal binder or compression stockings, and sleeping with the head of the bed raised should be considered (IIa); if symptoms persist, an alpha-agonist or a mineralocorticoid (IIa). The alpha-agonist raises BP both supine and upright. The mineralocorticoid promotes renal sodium retention and expands body fluid volume. According to the ESC, head-up tilt sleeping prevents nocturnal polyuria and reduces nocturnal hypertension. OH in treated hypertension: intensive antihypertensive treatment may increase the risk of OH, and in people with OH and risk factors for falls the ESC advises avoiding aggressive BP lowering. NICE recommends checking for postural hypotension in people with hypertension who also have type 2 diabetes, symptoms of postural hypotension or are aged 80 and over, and, in people with a significant postural drop or symptoms of postural hypotension, treating to a target based on standing blood pressure. The Russian Ministry of Health guideline recommends regular checks for OH in older patients, even without symptoms. The doctor chooses the treatment targets and regimen. ## When to call an ambulance Dizziness on standing can be a sign of bleeding or heart disease. What to do when someone faints is described in the article on [vasovagal syncope](../vasovagal-syncope/). **Call your local emergency number (112 in the EU, 911 in the US and Canada, 999 in the UK)** if dizziness on standing comes with: - blood in the stool or black, tarry stool; - difficulty walking, poor coordination or poor balance; - a fall or a faint; - chest pain or discomfort. Fainting can also be caused by heart disease. Call your local emergency number if the faint happened during exertion or while lying down, straight after a sudden fast heartbeat, or if new chest discomfort, breathlessness, abdominal pain or headache appeared together with it. **See a doctor as soon as possible** if dizziness on standing happens often or does not go away.