Ever feel light-headed or woozy when you get out of bed or up from a chair? That's because when you stand, blood naturally rushes to your legs and your blood pressure drops. Your body has to work harder to keep blood moving back up to the heart by boosting your blood pressure and heart rate for a few minutes.
Sometimes, it may take a moment (or several) to bring your blood pressure back to normal, and you might feel dizzy, confused, queasy, or have blurry vision until your body adjusts and catches up. Some people may even faint. These episodes of low blood pressure from standing up quickly are called orthostatic hypotension.
You're more likely to be affected when you're older. As you age, the cells in your heart and arteries that keep your blood pressure steady respond more slowly. And odds are you're taking medication for diabetes or heart disease, which can also play a role.
For many people, it happens only once in a while -- most often because you're low on fluids. When you're dehydrated, your body has a harder time making adjustments to control your blood pressure.
You may have mild dehydration if you've been exercising intensely, were outside in the heat or soaking in a hot tub, or are recovering from the flu, for example. Dehydration can be an ongoing concern if you have poorly controlled diabetes or if you take diuretics for high blood pressure.
After a Meal
Up to a third of older people are prone to dizziness after eating a large meal. Your intestine needs a lot blood to digest your food, which leaves less blood flowing in other parts of your body. When your body can't adjust for that, your blood pressure could drop and you may feel light-headed or take a tumble. Doctors call this postprandial hypotension.
Heart Disease and Other Medical Conditions
Since the problem is related to your blood pressure, it's not surprising that people with heart disease, heart valve problems, heart failure, or an extremely low heart rate (called bradycardia) can have this kind of dizziness.
A study of elderly women found that most with congestive heart failure would have a significant drop in their blood pressure when tested, and it would fall more than those without heart problems or other illnesses. About half had noticeable symptoms, too, while none of the other women did, even when their blood pressure fell.
Anemia (a condition where you don't have enough healthy red blood cells) or blood loss may be behind occasional dizziness.
Getting dizzy when standing can also be caused by the medication you take to treat heart conditions, including:
- ACE inhibitors
- Angiotensin receptor blockers (ARBs)
- Calcium channel blockers
- Diuretics, also known as "water pills"
If you take more than one of these drugs or drink alcohol while you're using them, it can raise your chance of dizziness.
What You Can Do
To help keep your balance, stand up slowly. Avoid crossing your legs when you're sitting for a long time. Don't stand still in one place; move your feet and legs to help keep your blood flowing.
Call your doctor if it's happening regularly or more often, or when it makes you feel faint. Some people may not feel dizzy right away. It could take more than 3 minutes after you stand up. This delayed orthostatic hypotension is a milder form, but a recent study suggests that people who have it may develop more symptoms over time.
Your doctor will work with you to figure out what's causing your dizziness and to treat any underlying conditions. He might adjust your medications to lessen your symptoms or recommend changes in your eating habits. You can also ask about wearing compression stockings. They apply gentle pressure to your legs, which will help push blood back toward your heart.