My son was on Singulair and has all the same symptoms discussed here--the aggression, self-loathing, has to sleep with my husband and me or is terrified, horrible nightmares, etc. He is on medication for them now after trying therapy for about six months. We finally decided on medication after we feared he'd actually hurt himself. (he made attempts, as much as a child knows how). I never connected it with Singulair, but the timing is right. He has been off of Singulair for at least a year to may-be even two years. I am wondering if this is only coincidence or if the Singulair could have caused lasting damage. He so fits what everyone else has described, even the words he says are almost exact--"I'm going to take a knife and kill myself." This from a seven year old. I would also love to hear if anyone else's child who has been off the medicine still has these symptoms.