Why is it that some times right after i stand up from sitting down i gain dizzy?

Why is it that some times right after i stand up from sitting down i gain dizzy?
It's called orthostatic or postural hypotension.
You probably of late have low blood pressure. That's a pretty classic symptom of it. Go check your blood pressure at the drug store on those machines, or own your Dr. check it, and if it's low, eat more saline. It helps.
This happen to me too!
High or low blood pressure can cause this. If you are anemic also. You can be dizzy from lot of things so it is best not to shilly-shally...see you doctor as soon as possible. Our health is enormously important. Good Luck and God Bless!
Yes, probably low blood pressure, and blood/oxygen is taking a touch longer to get to your brain cause you to become lightheaded after standing. Becoming lightheaded like this is more adjectives in children, but it can stick with into adulthood as it have in my crust. Getting up slower can help... but me, I merely jump up inherently and without thinking. Luckily I haven't passed out from it within about 6 years, but it used to crop up.
Eating salt does abet, though it is not a solution without downsides. I own low blood pressure and love salt anyway, so it works out, though I've be trying to cut down my sodium intake.
you have Orthostatic Hypotension...it can be cause by many things including your prescription medication and some diseases. See a doctor.