I fainted after a blood test and had a seizure. hospital ran tests said it was due to low blood test. what you think. i am 34 years old?

Syncopal epilepsy: When some people have blood taken or are surprised suddenly, they may have a syncopal episode. Some of these may result in a seizure which is not indicative of epilepsy. It results from a brief hypoxic spell (sudden reduction of oxygen or what is known as excessive vagus nerve stimulation. Work ups are usually negative. Anti seizure medications are not used.

Some advice: Those who faint and still stay somwhat upright or seated, and do not get to a prone or supine posture, will experience decreased brain blood flow and oxygenation due to blood pressure collapse. This can result in seizure activity. But, if you have blood drawn in a supine position and persist for several minutes, unlikely to either faint or seize.