Orthostatic Hypotension (Postural Hyoptension)

Orthostatic hypotension (also called postural hypotension) is a sudden fall in blood pressure that occurs upon standing quickly. Blood pressure is the force of your blood against the walls of your arteries (the blood vessels that carry blood from the heart through the body). Hypotension is the term for low blood pressure.

When you stand up, gravity pulls blood into your legs, and your blood pressure begins to fall. Certain reflexes in your body compensate for this change. Your heart beats faster to pump more blood, and your blood vessels constrict to prevent blood from pooling in your legs. Many drugs can affect these normal reflexes and lead to orthostatic hypotension. These reflexes may also begin to weaken as we age. For this reason, orthostatic hypotension is common in the elderly.

People with orthostatic hypotension feel dizzy when they stand up. The condition is often mild and lasts for just a few minutes after standing. Some people may faint (temporarily lose consciousness).

There are many causes for orthostatic hypotension. These include:

• dehydration
• anemia (low red blood cell count)
• a drop in blood volume (hypovolemia) caused by certain drugs such as thiazide diuretics and loop diuretics
• pregnancy
• heart conditions, such as a heart attack or valve disease
• old age: it is present in up to 20 percent of patients older than 65 (Lanier et al, 2011)
• diabetes, thyroid conditions, and other diseases of the endocrine system
• Parkinson’s disease
• long-term bed rest or immobility
• hot weather
• blood pressure medications and antidepressants
• using alcohol or drugs at the same time as blood pressure medications
• diuretics

The most common symptoms are dizziness and lightheadedness upon standing up. The symptoms will usually go away upon sitting or lying down.

Other common symptoms include:

• nausea
• palpitations
• headache
• weakness
• confusion
• blurred vision

Less common symptoms include:

If your doctor suspects that you have orthostatic hypotension, he or she will check your blood pressure while you are sitting, lying down, and standing. The doctor can diagnose orthostatic hypotension if your systolic blood pressure drops by 20 millimeters of mercury (mm Hg) or your diastolic blood pressure drops by 10 mm Hg within three minutes of standing up (Mayo Clinic, 2011).

The doctor may also conduct a physical examination, check your heart rate, or order certain tests to find the condition’s underlying cause. These tests may include:

• complete blood count (CBC) to check for anemia
• EKG (electrocardiogram) to check the rhythm of your heart
• echocardiogram
• stress test (measuring your heart rate during exercise)
• tilt table test (lying on a table that moves from horizontal to upright to test for fainting)

Treatment for orthostatic hypotension depends on the cause. Treatment may include the following changes in lifestyle:

• if you are dehydrated, you should increase your fluid and water intake and limit your alcohol intake
• stand up slowly when getting out of a chair or bed
• perform isometric exercises before getting up to help raise your blood pressure—for instance, squeezing a rubber ball or a towel in your hand
• if a medication may be the cause, your doctor may adjust dose or switch you to another medication
• wear compression stockings to help with circulation in your legs
• avoid crossing your legs or standing for long periods of time
• avoid walking in hot weather
• sleep with the head of your bead slightly elevated

For severe cases, your doctor may prescribe drugs that work to increase blood volume or constrict blood vessels to treat orthostatic hypotension (Cleveland Clinic, 2009). These include:

• fludrocortisone (Florinef), which is considered first-line therapy for orthostatic hypotension (Lanier, et al., 2011)
• midodrine (ProAmatine)
• erythropoietin (Epogen, Procrit)
• pyridostigmine (Mestinon)