Orthostatic Hypotension (Postural Hypotension)

Orthostatic hypotension is a sudden drop in blood pressure when you stand from a seated or prone (lying down) position. You may feel dizzy or even faint.

Orthostatic means an upright posture. Hypotension is low blood pressure. This type of low blood pressure is also called postural hypotension.

What is blood pressure?

Blood pressure measures the force of blood against artery walls as your heart pumps blood through your body’s circulatory system. Blood pressure includes two measurements in millimeters of mercury (mmHg):

• Systolic: Arterial pressure when your heart beats and fills arteries with blood.
• Diastolic: Arterial pressure when your heart’s at rest or between beats.

Your healthcare provider records blood pressure as systolic over diastolic. Healthy blood pressure for most people is below 120/80 millimeters of mercury. A reading below 90/60 millimeters of mercury is considered low blood pressure.

What BP is orthostatic hypotension?

There’s no set number for orthostatic hypotension. Healthcare providers define orthostatic hypotension based on individual blood pressure and how low it goes when you stand up. You have orthostatic hypotension if your blood pressure drops more than 20 millimeters of mercury in systolic pressure or 10 millimeters of mercury in diastolic pressure within three minutes of standing up.

Who might get orthostatic hypotension?

Anyone can get orthostatic hypotension. The condition becomes more common as you age. These factors increase your risk:

• Anemia or vitamin B12 deficiency.
• Dehydration from diarrhea, vomiting or diuretics.
• Endocrine problems, including diabetes, thyroid disease and Addison disease.
• Heart conditions, including arrhythmias and heart valve disease.
• Medications for high blood pressure (hypertension), heart disease and depression.
• Neurological problems, such as Parkinson disease and dementia.
• Pregnancy, especially during the first 24 weeks.
• Prolonged immobility because of illness, including pregnancy bed rest.

How common is orthostatic hypotension?

Orthostatic hypotension affects roughly 20% of older people, especially those who live in long-term care residences. It’s also common among people who’ve been on bed rest or given birth recently. Also, teens having growth spurts can experience orthostatic hypotension.