Today i passed out for 2 minutes after getting my blood drawn its never happened to me before why did this happen?

Vasovagal syncope: It is more common in young people. Difficult to explain in only 400 characters. Simply explained it is caused by a drop in heart rate and contractility leading to decreased cardiac output leading to low blood pressure and does not perfuse the brain adequately causing you to pass out.

Vasovagal syncope: What happened to you is common for some people. Vasovagal syncope is the medical term for passing out at times of being scared or anxious and the feelings we accumulate activate the vagus nerve which causes the heart to slow and blood pressure drops thus causing pt to pass out temporarily.

Vasovagal episode: Maria, You probably had a vasovagal episode. There is a web of nerves surrounding your veins that are part of a nerve called the Vagus nerve. The Vagus nerve is involved in a lot of body processes, in particular heart rate and blood pressure. Sometimes when a vein is poked, the nerve is activated, and your BP drops, depriving your brain of blood flow. The result is that you pass out briefly.