Every time I get up from sitting down, I nearly black out and get dizzy.
Even if i've only been sitting for less than a minute. As soon as i stand, everything is dark and cloudy for at least 5 seconds. Not head-rush because i don't get up too quick and havent been sitting long.. I also experience light heart palpitations.
You should definitely go see your primary care doctor about this issue as soon as possible. Dizziness and near fainting can sometimes be a a sign of a serious medical problem, and it always needs to be checked out. The fact that the symptoms always seem to occur when you are changing positions is somewhat reassuring, because it makes pooling of blood in your legs the most likely cause of the symptoms. This is the most benign cause of the symptoms, which can often be treated just by staying really well hydrated and by changing positions closely. Sometimes, however, dizziness with changing positions can be a sign of a more persistent dysfunction of the nerves which control the tone in your blood vessels, especially if you have diabetes or another reason to have chronic nerve dysfunction. Your doctor will also want to make sure that this is not a problem with your heart, especially given the palpitations that you sometimes report feeling. To do this, they will definitely want to check an electrocardiogram, and they may also want some additional heart testing. Finally, they will perform a complete neurological examination to make sure that this is not a problem with your central nervous system. Go see your doctor right away!
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