The person lies flat on a special motorized table for several minutes. If blood pressure does not decrease, the person is given isoproterenol a drug that stimulates the heart intravenously in a dose large enough to accelerate the heart rate by 20 beats per minute, and the test is repeated.
This procedure takes 30 to 60 minutes and is very safe. Any causes are treated when possible, including changing or stopping any causative drugs. However, many causes cannot be cured, and people must take measures to decrease their symptoms. Measures include lifestyle changes and drugs. People requiring prolonged bed rest should sit up each day and exercise in bed when possible.
People who are lying down or sitting should rise slowly and carefully. In general, it is helpful to consume adequate fluids, limit or avoid alcohol, and exercise regularly when feasible. Regular exercise of modest intensity increases the muscle tone in blood vessel walls, which reduces pooling of blood in the legs.
Sleeping with the head of the bed raised may help relieve symptoms. For some people, increasing salt intake may increase water retention and lessen symptoms. Doctors may recommend that people increase their salt intake by liberally salting food or taking sodium chloride tablets. However, increasing salt intake may not be recommended for people with heart disorders.
Doctors may give fludrocortisone , a drug that helps the body retain salt and water and thus prevent blood pressure from dropping when a person stands. However, this drug may cause high blood pressure when people are lying down, heart failure, and low levels of potassium in the blood. Sometimes doctors combine propranolol or another beta-blocker with fludrocortisone. Midodrine is a drug that narrows both arteries and veins, helping prevent blood pooling.
Side effects include tingling or numbness and itching. This drug is not recommended for people with coronary artery or peripheral arterial disease. Other drugs such as nonsteroidal anti-inflammatory drugs NSAIDs , droxidopa , pyridostigmine and octreotide may help in some cases.
It is more common among people with coexisting disorders, especially high blood pressure, and among residents of long-term care facilities. Many falls may result from dizziness when standing. Older people should avoid prolonged standing. The increased incidence in older people is due to decreases in the responsiveness of the receptors that manage blood pressure plus increases in arterial wall stiffness, which make it more difficult for arteries to move more blood to increase blood pressure.
Decreases in receptor responsiveness delay the normal heart and blood vessel responses to standing. Paradoxically, high blood pressure, which is more common among older people, may contribute to poor receptor sensitivity, increasing vulnerability to dizziness when standing.
Dizziness or light-headedness when standing typically involves a decrease in body fluid volume or autonomic nervous system dysfunction. Aging often causes some degree of autonomic nervous system dysfunction, but doctors examine all affected people to ensure that no nervous system disorders are present.
Treatment involves physical measures to reduce venous pooling, regular exercise, increased salt intake, and sometimes fludrocortisone or midodrine. Merck and Co. From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world. The Manual was first published in as a service to the community.
Learn more about our commitment to Global Medical Knowledge. This site complies with the HONcode standard for trustworthy health information: verify here. Depending on the cause, it may not be a long-term problem. But if you feel faint or actually lose consciousness, talk to your doctor as soon as possible.
Crispell, certified registered nurse practitioner at ConvenientCare in Wilkes-Barre. People who experience presyncope usually dismiss it and move on with their day. Especially because dizziness can be a symptom of an underlying medical condition. Also called postural hypotension, this is the head rush you sometimes feel when you stand up. This condition also known as an abnormal heart rate is when your heart beats too fast, too slow or in a way that causes a sudden decrease in the blood supply to your brain.
Any of these can make you feel faint. Medicines prescribed for pain, heart conditions and high blood pressure can affect your circulatory system and — you guessed it — feeling dizzy. If it happens a lot, talk to your doctor about adjusting your dosage. Not drinking enough fluids can cause nausea, weakness, dizziness, low blood pressure and fainting.
The good news: Rehydrating will alleviate your symptoms quickly. Anemia is a lack of healthy red blood cells or hemoglobin in your blood, which carry oxygen to your organs — including your brain. Sign up to receive the latest health and science news, plus answers to wellness questions and expert tips.
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