Overview

Postural hypotension (also called orthostatic hypotension) is a drop in blood pressure when you stand up after lying or sitting down. This can make you feel dizzy and can even cause you to faint.

You might:

• feel lightheaded or dizzy when you stand
• have blurred eyesight
• feel weak
• faint
• feel or be sick

Causes of postural hypotension

There are several possible causes of postural hypotension.

• Dehydration. Not drinking enough fluids (dehydration) reduces the amount (volume) of blood circulating through your blood vessels. This can lower your blood pressure.
• Heart conditions. Some heart conditions lead to low blood pressure and prevent your body from pumping blood quickly when you stand up. They include conditions causing a slow heart rate or heart failure.
• Hormone (endocrine) problems. Some hormone problems, such as low thyroid levels or uncontrolled diabetes, make it harder for your body to control blood pressure.
• Conditions affecting the nervous system. Some conditions that affect the nervous system, such as Parkinson's disease, make it harder for your body to control blood pressure.

Diagnosing postural hypotension

Your GP can do simple tests to diagnose postural hypotension. They include:

• measuring your blood pressure when you lie down and stand up
• doing blood tests to check your thyroid levels and sugar levels

Your GP might refer you for more tests, including:

• an electrocardiogram (ECG) (a simple test to check for any problems with your heart's rhythm)
• a tilt table test (when you lie on a couch that slowly tilts up and down while your blood pressure and heart rate are monitored)

Treatment for postural hypotension

If you have postural hypotension, there are some things that you can do to help your symptoms.

Lifestyle changes

Drinking more fluids but less caffeine might reduce the symptoms of postural hypotension.

Reviewing your medicines

Some blood pressure medicines can make you more likely to get postural hypotension. A GP can review your medicines and change them if needed.

Medicine to treat postural hypotension

A medicine called fludrocortisone can increase your blood pressure and reduce the effects of postural hypotension. If you take this medicine, your GP needs to monitor you closely and make sure that it does not cause high blood pressure.

Standing up slowly

Take your time when you stand up. Sit down again if you feel dizzy.