If you are the type that drinks a lot of water, you will certainly need to pee in the middle of the night, but you will have to reconsider that after reading this.
Orthostatic hypotension occurs when a person’s blood pressure falls when suddenly standing up from a lying or sitting position. It is the lowering of blood pressure when going upright from a laying down position causing you to feel dizzy.
It occurs predominantly by delayed constriction of the lower body blood vessels, which is normally required to maintain an adequate blood pressure when changing position to standing. As a result, blood pools in the blood vessels of the legs for a longer period, and less is returned to the heart, thereby leading to a reduced cardiac output. Severe drops in blood pressure can lead to fainting with a possibility of injury, sometimes it leads to death.

When you wake up from a deep sleep forcefully, it’s not every part of your body that wakes up at the same time. Some wake up first why others follow, the brain is a busy part of the body, and it is always awake when others are sleeping just to remind them that they will still need to wake up after some hours.
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