Orthostatic Intolerance (OI) occurs when the individual is standing or sitting up. In 1995, a link between OI and Chronic Fatigue Syndrome (CFS) was observed at Johns Hopkins University. In some cases up to 97 percent of Chronic Fatigue Syndrome patients in studies have some form of OI, particularly young people.
Two forms of orthostatic intolerance are neurally mediated hypotension (NMH) and postural orthostatic tachycardia syndrome (POTS). NMH is a dramatic drop in systolic blood pressure while standing. Other symptoms will often increase as well. POTS is increased heart rate within 10 minutes of standing. It's also called chronic orthostatic intolerance (COI).
Symptoms that accompany neurally mediated hypotension and postural tachycardia syndrome include dizziness, tremors, lightheadedness, visual disturbance and breathing difficulties. Swollen, bluish legs will indicate that blood is pooling. A hot environment can increase these symptoms.
"Unlike those with OH, which occurs within the first three minutes of standing, CFS patients with NMH or POTS often have a delayed form of orthostatic intolerance, meaning that heart rate and blood pressure changes don't develop for many minutes after standing, making the standard in-office test for acute orthostatic hypotension ineffective in diagnosis. "
http://www.cfids.org/about-cfids/orthostatic-intolerance.asp
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I have all of these symptoms but I have high blood pressure. My blood pressure was always very low before CFS. I attribute the the high BP to loss of exercise and weight gain which set in a year or so after getting sick. I used to get those short low BP dizzy spells after standing but now it's more like whats described in the article dizzy, lightheaded etc. after a few minutes. I also get the same symptoms after eating. Just curious if anyone else has the same experience after meals.
June 2, 2010 - 12:18pmThis Comment
As to blood pressure, many of us have dysregulated blood pressure due to a glitch in our autonomic nervous systems so you may have both high and low at different times.
Dizziness and lightheadedness can be a result of a sudden drop of blood pressure upon standing and for some reason many of us will get that in a delayed reaction after being on our feet 10 min. or so.
If this happens after eating, I'm wondering if you might have food sensitivites you're unaware of. If you feel worse after eating, this can be the reason -- or one of the reasons.
Sorry all I can offer is generalizations but I thought I'd write them in case any of them fit.
June 6, 2010 - 4:17pmThis Comment