My son Colin who is 9 has been on Singulair for about two years n...

My son Colin who is 9 has been on Singulair for about two years now and I am getting very concerned about him. It started a few months back where the school nurse sent him home a couple of times because of an unexplained hives only on his hands. Every time the dog scratches him, the scratches swell . Yesterday he had red blotches just around his mouth. We are talking about an extremely shy boy who all of the sudden will not listen to the school teacher. He lashes out and goes into these unexplained rages.He complains of stomach pain and is nauseas all the time.He does get headaches and seems depressed.Last weekend and this weekend, friend of ours experienced the whole freaked out incident. One minute Colin will be fine, the next minute seems like a panic attack. I really was starting to believe it was behavioral but I now am convinced it is his medication Singulair!!