Orthostatic hypotension (postural hypotension): causes, symptoms and treatment

The NHS says if a cause for low blood pressure can be found, a GP will recommend treatment to ease symptoms. Examples include changing medicines or altering the dose if that is the cause, and wearing support stockings, which can improve circulation and increase blood pressure. It says medicine to increase blood pressure is rarely needed because simple lifestyle measures or treating the underlying cause is usually effective.

The BHF adds that, where needed, medicines can be used depending on the cause. It names beta-agonists or alpha-agonists, and fludrocortisone, a steroid that makes the kidneys retain water and salt and so increases blood volume. These are prescribed by a doctor after assessment.

• Review of medicines that may be lowering blood pressure, by a GP.

• Support stockings, if suitable (the BHF says to ask your doctor first).

• Drinking more fluids, unless you are on a fluid restriction, in which case check with your doctor.

• Raising your legs.

• Medicines such as fludrocortisone in selected cases, prescribed by a doctor.

The BHF explains that when blood pressure drops, your heart rate usually increases and blood vessels constrict to maintain it. If the heart rate does not increase enough, or the vessels do not constrict enough, blood pressure falls. Standing up from sitting or lying is one situation in which this shows up, and it can also happen after eating, as more blood flows to the digestive system.

The BHF lists medicines, medical conditions and loss of blood volume as causes. The NHS adds that low blood pressure can be due to being fit and healthy, inherited, developing with age, pregnancy, some medical conditions such as diabetes and some medicines.

Orthostatic hypotension and postural hypotension are the same thing. The NHS says that if you get symptoms when you stand up or suddenly change position, you may have this type of low blood pressure. The NHS defines low blood pressure as a reading of less than 90/60mmHg, and the BHF notes the NHS guide of under 89/59 for low and 90/60 to 120/80 for normal.

Blood pressure varies during the day and with what you are doing, the NHS says. A single low reading with no symptoms is not necessarily a problem, but symptoms that keep happening should be checked.

The BHF says most people with low blood pressure do not notice symptoms. When symptoms occur, the NHS and BHF list the following. The NHS says to get your blood pressure checked if you keep getting symptoms like these.

• Light-headedness or dizziness, particularly when standing up or changing position.

• Feeling sick (nausea).

• Blurred vision.

• Feeling weak.

• Difficulty concentrating or confusion.

• Fainting.

The NHS lists things that can help with symptoms of low blood pressure. For fainting, the NHS also gives steps if you feel you are about to faint: lie down with your legs raised, or sit with your head lowered between your knees, drink some water, cross your legs while standing or rock on your toes, and clench your fists.

• Get up slowly from sitting to standing.

• Take care getting out of bed: move slowly from lying to sitting to standing.

• Eat small, frequent meals; lying down or sitting still for a while after eating may help.

• Increase the amount of water you drink.

• Avoid sitting or standing for long periods.

• Avoid bending down or changing posture suddenly.

• Avoid drinking too much alcohol.

The NHS says to see a GP if you keep getting symptoms of low blood pressure such as dizziness and fainting. It says you can have your blood pressure checked by a pharmacist, practice nurse or GP, or at home with a monitor.

The NHS fainting page says you should see a GP if you have fainted. Call 999 if the person is not breathing, cannot be woken within 1 minute, has not fully recovered or has difficulty with speech or movement, has chest pain or palpitations, has seriously hurt themselves, is shaking or jerking, fainted while exercising or fainted while lying down. It also says you must tell the DVLA if you are fainting regularly.

On the NHS, a GP can measure your blood pressure lying and standing, review medicines and look for underlying causes, referring to cardiology, geriatrics or neurology if the cause is not clear or symptoms are severe. The NHS says you can also ask a pharmacist to check your blood pressure.

Private cardiology and general medicine appointments can arrange blood pressure monitoring and tests, usually self-paid. Medicine changes should be agreed with the prescriber, rather than stopping tablets yourself.