It might be orthostatic hypotension, a condition that can be challenging to catch and treat.
You stand up and suddenly feel unsteady on your feet. It's easy to brush off this experience as a fluke or a bug, but don't. You may have a condition called orthostatic hypotension, a temporary drop in blood pressure when you stand. It's tricky to catch.
"Blood pressure is highly variable, and depends on position, timing, the method of measurement, and circumstances associated with its measurement," says Dr. Lewis Lipsitz, chief of gerontology at Harvard-affiliated Beth Israel Deaconess Medical Center and director of the Marcus Institute for Aging Research at Hebrew SeniorLife. "It may take multiple blood pressure measurements at different times of day, lying and standing, in order to detect orthostatic hypotension," Dr. Lipsitz says.
Why it happens
When you stand, blood rushes to your abdomen and legs, and away from your head and brain, simply because of gravity. Your body's autonomic nervous system senses this and alerts the brain to make the heart beat faster and narrow your blood vessels. That restores normal blood flow to your brain and elsewhere.
But over time, the system can weaken. Heart rate may not increase and blood vessels become stiffer and less able to adapt. Blood pressure may also fall if you're dehydrated or taking medications that affect heart rate or blood vessel function. Some diseases (such as Parkinson's disease and diabetes) can also contribute to the problem.
The result is that standing up reduces blood flow to the brain, causing lightheadedness, blurred vision, or fainting. Fortunately, the condition is mild in most people: you just need to be careful when sitting up or standing up, ready to sit back down if you feel you might faint. Some people don't have any lightheadedness, but fall anyway.
How to monitor your blood pressure at home
You don't have to wait for a doctor appointment to monitor your blood pressure. An automatic monitor that doesn't require a stethoscope is easy to use and widely available in drugstores or online for $50 to $100. You may need to ask your doctor or nurse to help you calibrate it first (to make sure it's accurate) and help you learn to operate it.
For general monitoring, take your blood pressure once or twice per month (or when your doctor recommends). The best times are early mornings, after meals, and evenings.
To ensure accurate readings:
If you have orthostatic hypotension, check your blood pressure a few times per week, either in the morning or evening. Each time, get at least two different measurements: one measurement while lying down, and one while standing up.
Wait a few minutes in between each reading for your blood pressure to stabilize.
If you notice big changes in your blood pressure, report them to your doctor. "But don't take your blood pressure too often. It's not helpful, and it may increase stress or anxiety, which isn't good for your heart or blood pressure," suggests Dr. Randall Zusman, a cardiologist with Harvard-affiliated Massachusetts General Hospital.
And remember: home monitoring should not replace regular visits to your doctor.
What's the fix?
When orthostatic hypotension is more severe, treatment can be challenging. "Standing blood pressure may be very low, while lying blood pressure may be very high," Dr. Lipsitz explains.
He recommends treatments ranging from wearing compression stockings and elevating the head of the bed to reduce overnight blood pressure, to medications such as midodrine (Orvaten, ProAmatine) and fludro-cortisone (Florinef).
What else helps for this low blood pressure condition? "I start with a high-salt diet, then add fludrocortisone, then add nonsteroidal anti-inflammatory medications such as ibuprofen [Motrin, Advil] to force fluid and salt retention," says Dr. Randall Zusman, a cardiologist with Harvard-affiliated Massachusetts General Hospital.
A few final tips: "Drink at least one or two quarts of fluid daily to prevent dehydration, keep moving your legs when you're upright, and maintain good muscle strength in your legs," Dr. Lipsitz suggests.
Image: © Dean Mitchell/Getty Images
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