Sunday, September 4, 2011
Black Spots & Blurred Vision- Sometimes a Simple Fix
Have you ever stood up quickly and seen black spots in front of your eyes? The room sways and you might think you are going to pass out, but then it all clears in a few seconds. What's going on? The medical term is "orthostatic hypotension". When you change from lying down or sitting to standing, your blood pressure should increase enough to keep blood flow constant to your brain. When the pressure is not adequate, that's when these symptoms of blurred vision and lightheadedness occur.
What makes it happen? The most common cause for an isolated incident of this in a healthy person is DEHYDRATION. Think about the process like a garden hose filled with water and held upwards. The less water in the hose, the more pressure it will take to push the water to the top, right? You have to squeeze in on the sides of the hose more, or increase the pressure pushing up to get the water to flow upwards. Your blood vessels work the same way, so if your blood volume is depleted from dehydration, voila- not enough blood makes it to your head! The good news here is that simply increasing your water intake will fix the problem.
This process can also be the result of faulty "squeezing" mechanisms, which can occur in diseases like diabetes or Parkinson's disease. Medications can also be the culprit, especially blood pressure , antidepressants and pain pills. How can your doctor test for this process? Often simply taking your blood pressure sequentially in lying, sitting and standing positions will give us the answer. If your systolic pressure (the top number) drops more than 20mm Hg or bottom number drops more than 10mm Hg when standing compared with sitting, you've got orthostatic hypotension. Sometimes more sophisticated testing is required, but the vast majority of the time, these simple office readings are enough.
BOTTOM LINE: If you are getting lightheaded or having temporary blurred vision when you stand up, grab a glass of water- drink it- and call your doctor to schedule an appointment to figure out the cause & cure for your symptoms.