Low Blood Pressure (Orthostatic Hypotension)
What is orthostatic hypotension (low blood pressure)?
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. The condition is also called postural hypotension.
What is blood pressure?
Blood pressure measures the force of blood against artery walls as the heart pumps blood through the body’s circulatory system. Blood pressure includes two measurements. Each is calculated in millimeters of mercury (mmHg):
- Systolic: Arterial pressure when the heart beats and fills arteries with blood.
- Diastolic: Arterial pressure when the heart is 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 mmHg. A reading below 90/60 mmHg is considered low blood pressure.
Healthcare providers define orthostatic hypotension based on individual blood pressure. You have orthostatic hypotension if your blood pressure drops more than 20 mmHg in systolic pressure and 10 mmHg 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 the risk:
- Anemia or vitamin B12 deficiency.
- Dehydration from diarrhea, vomiting or diuretics.
- Endocrine problems, including diabetes, thyroid disease and Addison’s disease.
- Heart conditions, including arrhythmias and heart valve disease.
- Medications for high blood pressure (hypertension), heart disease and depression.
- Neurological problems, such as Parkinson’s disease and dementia.
- Pregnancy, especially during the first 24 weeks of pregnancy.
- Prolonged immobility due to illness, including pregnancy bed rest.
Are orthostatic hypotension and postural tachycardia syndrome (POTS) the same condition?
Postural tachycardia syndrome, or POTS, causes symptoms similar to orthostatic hypotension. Both cause dizziness or fainting upon standing. Along with a drop in blood pressure, POTS causes a heart rate increase of 30 to 40 beats per minute within 10 minutes of standing. POTS is less common than orthostatic hypotension.
Symptoms and Causes
What causes orthostatic hypotension?
When you’re seated or lying down, blood from veins in your legs flows easily to the heart. When you stand up, blood in your lower extremities has a harder time reaching your heart. There’s less blood available for your heart to send to organs and muscles. As a result, blood pressure temporarily drops.
What are the symptoms of orthostatic hypotension?
Orthostatic hypotension happens more frequently — and with more severe symptoms — in the mornings. That’s because blood pressure is at its lowest in the morning.
Some people don’t experience any symptoms from orthostatic hypotension. Others find that hot temperatures (from the weather, a fever or even a hot tub or shower) make symptoms worse.
Other signs include:
Diagnosis and Tests
How is orthostatic hypotension diagnosed?
Your healthcare provider will check your blood pressure while you’re seated, lying down and standing. You may also get one or more of these tests:
- Blood tests to check for conditions like diabetes and anemia.
- Echocardiogram (echo) to check the heart’s pumping action.
- Electrocardiogram (EKG) to test for heart rhythm changes.
- Exercise stress test to measure heart rate during physical exertion.
- Portable EKG devices (Holter monitor) to measure heart rhythm.
- Tilt table test to safely measure blood pressure, heart rate and heart rhythm while you lie on a table that moves from horizontal to vertical.
Management and Treatment
What are the complications of orthostatic hypotension?
People with orthostatic hypotension may have a higher risk of:
- Bone fractures or concussions due to falls when you feel dizzy or faint.
- Postprandial hypotension, low blood pressure 30 minutes to two hours after eating (particularly a high-carbohydrate meal).
- Shock or organ failure if blood pressure stays too low.
- Stroke or heart disease caused by fluctuations in blood pressure.
- Supine hypotension, low blood pressure that occurs when lying down.How is orthostatic hypotension treated?
How is orthostatic hypotension managed or treated?
If you have episodes of orthostatic hypotension, your healthcare provider will first try to determine if you have another condition or disease that is causing it. In many cases, treating the disease that is causing the orthostatic hypotension will cure it.
If you’re taking a medication known to cause orthostatic hypotension, your provider may change the dose or switch you to a different drug. Rarely, people with orthostatic hypotension need medications to increase blood volume and pressure. These medications include:
- Droxidopa (Northera®).
- Erythropoiesis-stimulating agents (ESAs).
- Fludrocortisone (Florinef®).
- Midodrine hydrochloride (ProAmatine®).
How can I prevent orthostatic hypotension?
If you’re prone to orthostatic hypotension, these steps can reduce symptoms:
- Keep your temperature moderate: Don’t take very hot baths or showers.
- Stay hydrated: Drink plenty of water, limit alcohol and avoid heavy, high-carbohydrate meals.
- Don’t sleep flat: Elevate your head at night by using more pillows or tilting the mattress.
- Prepare before standing: Give yourself more time to move into a standing position after sitting or lying down. Have something sturdy nearby to hold onto when you stand up.
- Move your muscles: March your feet if you must stand for prolonged periods. Do isometric exercises (squeeze a soft rubber ball or towel, or clench and unclench your hands) to raise blood pressure before standing.
- Support blood pressure: Wear compression stockings or an abdominal binder to improve blood circulation and pressure.
Outlook / Prognosis
What can I expect if I have orthostatic hypotension?
Most people with orthostatic hypotension can manage symptoms by taking preventive steps. For example, you may need to move more slowly into a standing position. The condition rarely causes long-term problems.
When should I call the doctor?
You should call your healthcare provider if you experience:
- Chest pain.
- Falls or fainting.
- Suspected bone fractures or head injuries due to falls.
- Signs of shock (cold, sweaty skin, rapid breathing, blue skin tone and weak pulse).
What questions should I ask my doctor?
You may want to ask your healthcare provider:
- Why did I get orthostatic hypotension?
- What is the best treatment for orthostatic hypotension?
- Could medications be causing my symptoms? Should I change medications?
- What changes should I make to manage symptoms?
- Should I look out for signs of complications?
A note from Cleveland Clinic
Orthostatic hypotension symptoms can be unsettling. They may even be dangerous if you lose your balance, fall or pass out. Symptoms often improve when you change how you move into a standing position. Tell your healthcare provider about your symptoms. You may need to change your medications to reduce or prevent symptoms. In more severe cases, your provider may prescribe medicine to improve blood flow and pressure.