why do you get dizzy if you stand up too fast?

Answer 1

The answer as some people have already mentioned is blood rushing out of your brain. The amount of oxygen and glucose dramatically decreases and you pass out because your brain cells don't have enough of it --- hmm I wonder if that is true?? I mean when you get up to a standing position you instantaneously feel dizzy and in severe cases you pass out immediately. I cannot image that our brain cells cannot withstand a few seconds of low oxygen and glucose. The other thought is whether the actually drop in blood pressure causes some reflex in our body to shut your brain down and make you pass out. Evolutionary this would make sense. Since by passing out ie laying on the ground blood flow to the brain returns because when you are laying down gravity is not working against blood flow to you brain. So the concensus is blood rushing out of the brain but I'm not entirely clear based on the above answers anyone knows the exact mechanism of how this occurs.

Answer 2

When you stand up quickly gravity pulls blood from your brain towards your feet and blood doesn't return to the brain until the next heart beat. With a slow pulse, this takes a second or two and that is enough time to feel the lack of oxygen in the symptom of lightheadedness or dizziness. It is also related to something called postural hypotension. This results from a decrease in blood flow to the brain, due to a drop in blood pressure upon standing up.

As long as it occurs only occasionally, you don't really need to worry. If you have constant and severe dizziness with changing position you should see a doctor to rule out an underlying condition such as an irregular heartbeat.

Answer 3

Standing Up Too Fast

Answer 4

This Site Might Help You.

RE:
why do you get dizzy if you stand up too fast?

Answer 5

My heart rate at rest use to be like 42 beats a minute when I was in great running shape and when I got up off of the coach and ran into the kitchen I would get so dizzy that I would black out. The Doctor said I was in great shape and that everything was fine, that I just needed to slow down when I got up. I believe it had to do with blood movement in the body.

Answer 6

I have the same thing and also when light juts my eyes everythong turns black and I feel dizzy and I end up falling then once I fall eveything goes back to how it was and yes its becuase you need water or you just need to wait a little or stand up slower.

Answer 7

Definitely! Without the pleasures of an alcoholic drink. The blood to your head rushes when you do a quick movement,
so, naturally, dizziness is expected.

Answer 8

I think the blood rushes from your head too fast.

Answer 9

it is called postural hypotension.. whereby, due to getting up suddenly to a upright position, there is lower blood supply to th head. its of no significance if it happens rarely , like lets say once a month. but if u are suffering from this problem on a day to-day basis, u better seek the advice of a physician.

Answer 10

the blood in your brain suddenly rushes down, so it has less blood so suddenly, and it makes you dizzy.