17 Year Old Male, Suddenly Passes Out Cold, Then Goes

17 year old male, suddenly passes out cold, then goes into seizure but thrashes instead of tensing up. Gasping for air while thrashing. Bout may last 10-15 minutes. Emergency aid called every time with no conclusion after tests run at hospital. Does not occur regularly, about once every couple months. Boy does not remember nor feel any symptoms prior to bout. Major headaches follow for a couple of days after experience. Epilepsy was not considered a factor because of a lack of tension while suffering episode. Boy is hemophiliac. Otherwise is healthy, athletic and energetic.