why is it that when you stand up too fast sometimes you feel like you’ve been hit in the head and are on the verge of seeing stars? and why do people see stars when they get hit in the head?
This is called orthostatic hypotension. It’s basically a sudden drop in blood pressure when you suddenly stand after sitting or lying down for a period of time. From what I’ve heard, it might be a sign of a bigger problem, it may be a withdrawal symptom for alcoholics, or it might be a temporary “no big deal.”
http://www.tchain.com/otoneurology/disorders/medical/orthostatic.html
The above link seems to concentrate on the scarier causes. However, it’s pretty common, and harmless, if you’re tall and in your teens.
While I agree that it’s pretty common, and much of the time it probably is harmless, please don’t always assume it’s harmless, even “if you’re tall and in your teens.” Tall teens can have some of the conditions listed in that scary link. Here is one that’s not so scary:
i’m short, and in my teens.
Here are some tips from decades of personal experience. As you know, the trouble comes from a shortage of fresh blood to your brain. You need to counteract that as soon as possible.
When possible, the simplest way is to get the head lower than the heart. Bend over and look down. If needed, you can disguise this by untying and retying your shoe. If you feel near to passing out, go on down to one knee & put your hands on the ground. If you pass out, you won’t have far to fall.
When you can’t bend down, there are other ways to get more blood to your head. Muscles can act as pumps; there’s always some idle blood waiting in the veins in the legs, and when you tense the leg muscles, they squeeze the veins.
Spare blood is also in slack vessels of your digestive tract. Take a deep breath to push down on them, and pull in your belly (trying to pull the belt buckle toward the spine.
If convenient, raise one or both arms up. Some blood will drain out of the arms
Pay attention to the symptoms. Learn how your eyes feel, what your ears sound like, and where your vision start to get grainy at the edges. The earlier you respond to the early signs, the less severe the occurance will be.
This thing might go away with age, or it might not. Mine never did, and I’m 54. Learn to control it, don’t let it control you.
I thought this was just a form of vertigo. In particular, this has happened to me many times (although not recently), and it was diagnosed as “benign positional vertigo.” It might not be precisely what the OP is experiencing, though.
I usually get that after a lack of caffiene. Either way, if I can remember after sleeping, I usually lay in bed for a second or two, take some deep breaths, and then stand up while taking a deep breath at the same time. The trick here is to get oxygen in the blood and to get your heart pumping quicker. So when you stand up, the required oxygen is getting to your head, much quicker and satisfying the oxygen requirements of your brain.
I get this all the time. Usually it passes in a matter of seconds. A couple of times I got close to fainting so I lay down with my feet up and after a few minutes, I am good as new!
I used to get that a lot. Usually I’d stay standing, but sort of lean against something and keep my head down a bit. Eventually my body realized it was going to have to get that blood back up to my head, and all was well from that point on. I’m not sure whether I grew out of it or whether it just went away because I’m a lot better hydrated now.
As has already been stated, that lightheaded feeling is a result of too much oxygen-rich blood vacating your brain. It takes a few seconds for everything to re-equalize upon arising, and lightheadedness is the result. I have low blood pressure and the effects of standing up too quickly are especially brutal for me; I’ve even fully passed out a time or two.
I’ve developed a method to combat it similar to AskNott’s description, but different enough to warrant mentioning. Upon watching a show about fighter pilots and the loss of conscience they suffer at high g forces (same root cause: lack of blood in the brain), it occured to me I could employ the same techniques they’re taught to use: clinching and breathing.
Upon standing quickly, clinch your stomach muscles hard, like you’re preparing to get slugged in the gut; this will constrict the flow of blood to your lower extremities. While you keep your stomach tightened as hard as you can, take rapid, short, lamaze-style breaths; this will super-oxygenate incoming blood. (Be sure not to do this too long, though, as hyperventilating can make you just as lightheaded. I find five or six breaths does the trick for me.)
Since starting the technique, I’ve not become so much as lightheaded, let alone passed out. Hope it works for you!