text: i had a seizure and the doctors dont know why...any ideas? yesterday morning about 5-10 minutes after i woke up, all of a sudden i became extremely dizzy and i blacked out. the moment i hit the floor i went into a hypofusional seizure that lasted about 15-30 seconds. when i gained back conciousness after seizing for about 15 seconds, i was still in the seizure, yet very calm and immidiately aware of what was happening.  i have never had a seizure before and i'm only 13 years old, and when i was taken to the hospital, i was put through a catscan and the doctors didnt find anything abnormal.  i have just started taking cingulair 5mg pills once every night about 3 weeks ago for my asthma, and i dont know if that could have anything to do with the sudden drop of blood pressure.  my father took my blood pressure less than 3 minutes after my seizure and it was 76/36. the normal blood pressure is about 120/60.  i wasn't dehydrated and my blood sugar was normal and i am not a diabetic.  any ideas why my blood pressure dropped so low suddenly? have they checked all your electrolytes?  perhaps just a vasovagal response?