What Is Orthostatic Hypotension?
Orthostatic hypotension often comes as a nasty surprise right after people start taking a blood pressure medication. When the victim of orthostatic hypotension stands up from a seated position, blood rushes away from the brain and he or she can feel woozy—or even fall flat on the face. The causes of orthostatic hypotension, however, are not limited just to medication.
In orthostatic hypotension, the heart simply does not pump with enough pressure to send blood to the brain when the person stands up. Fainting may be immediate, when the heart does not respond to standing up at all, or 1 to 3 minutes later, as the heart struggles to keep up with the demands of the change of the body's position.
The most common cause of orthostatic hypotension is treatment with a class of medications for high blood pressure known as beta-blockers. These drugs keep the heart beating at a slow, steady pace. The first days a person uses these medications the heart simply may not accommodate a quick move from sitting or lying down to standing up. It may be necessary to get up gradually or to find nearby objects for support—or a soft landing. It is not unusually for the blood pressure to fall by 30 mm Hg in just a few seconds.
Orthostatic Hypotension and POTS
When orthostatic hypotension occurs in people who are not taking high blood pressure medication, the most frequent diagnosis is POTS, postural orthostatic tachycardia syndrome. In POTS, the heart races when the person moves in a standing position. The resulting change in blood pressure may or may not be enough to prevent a faint.
POTS is usually accompanied by a number of additional symptoms. There can be decreased sweating, an outward bulging of the eyes, and, in males past puberty, delayed ejaculation during sexual intercourse. There can be constipation, flatulence, and retained urine. It is not unusual for people with POTS to complain of blurred vision, lightheadedness, anxiety, nausea, shallow breathing, abdominal pain, and period of profuse sweating for no apparent reason although perspiration is generally limited.
POTS usually begins when people are in their 30's. There commonly is a trigger, usually some relatively severe infection accompanied by fever. The heart beats fast, but blood pressure does not fall significantly, far less than the 30 mm Hg drop in blood pressure common when orthostatic hypotension is caused by medication. Doctors usually refer to POTS as "self-limiting," but this is primarily because they do not treat it.
Orthostatic Hypotension and More Serious Conditions
There are some diseases for which orthostatic hypotension is an early warning sign. Multi-system atrophy, also known as Shy-Drager syndrome, often has orthostatic hypotension as an early symptom, but other devastating symptoms quickly follow. There are also some autoimmune conditions that cause orthostatic hypotension, but these also cause dry mouth and dry eyes.
Orthostatic Hypotension in Kids and Teens
Children and teens, of course, usually do not take high blood pressure medication. When episodes of orthostatic hypotension occur in kids and teens, the most common cause is a condition known as orthostatic intolerance. In simple terms, orthostatic intolerance is passing out when standing too still for too long.
When passing out is preceded by nausea, vomiting, heat exposure, or a hard workout, a doctor is likely to diagnose the disease as a "simple faint," although most will run additional tests just to be sure. If a child or teen's faint is accompanied by tachycardia, or rapid heartbeat, or by unusual changes in blood pressure, the doctor will run at least an electrocardiogram (EKG) to make sure the heart is in good rhythm. In some children and teens, passing out when moving from a seated position to a standing position is a sign of a condition known as long QT syndrome. In this condition, passing out can even lead to death.
What You Can Do About Orthostatic Hypotension
The most important thing you can do about orthostatic hypotension is to make sure you are only suffering POTS or a reaction to medication. Other, more serious conditions may be ameliorated with early treatment. Teenage athletes, in particular, have to be examined to rule out long QT syndrome.
If your fainting spells are due to medication, insist that your doctor prescribe a different medication. There are many ways of treating high blood pressure. These simple steps will also be helpful.
- Increase salt and fluid intake. Drink no less than eight glasses of water every day.
- Consider support stockings and abdominal binders to help keep blood flowing upwards. Even antigravity suits may be prescribed in some cases.
- Avoid heavy meals. A full stomach interferes with blood circulation.
- Avoid constipation. Straining during bowel movement is a common cause of passing out. If you feel yourself passing out while you are seated on the commode, stop trying to have the bowel movement immediately. Lower your head down to your chest so your heart does not have to pump blood as high, and wait—maybe as long as half an hour—for the episode to pass.
- Dietary fiber, introduced gradually, helps make stools softer and easier to pass. If you have a problem with heartburn or gastroesophageal reflux, oat bran will be easier for you to tolerate than wheat bran. Water-soluble fiber will be easier for you to tolerate than insoluble fiber. Don't eat prunes or take harsh laxatives. The combination of hard stools and an urgent need to have a bowel movement greatly increases your risk of postural hypotension.
- If you have decreased sweating, limit your physical activity during hot weather. Spritz yourself with cool water from time to time if you have to go outdoors during extreme heat.
- Elevate the head of your bed. Don't stay completely flat on your back for too long.
- And, finally and most importantly, whenever you are in a seated position, get up slowly. The extra second or two you spend moving from a seated position to a standing position may give your heart a chance to keep blood flowing to your brain and prevent embarrassment or injury.