Singulair and wishful thinking

My son is 10 ½, and had been on Singulair for almost 6years to treat his well controlled asthma and allergies. We have had behavior problems with him for years, but it seems to have gotten worse this school year, when his grades (he is in the gifted program at school) went down the tubes. Our family has been to counseling, where it was suggested we put him on ADHD meds. We resisted, but things had reached the point that I was ready to give the NEW meds a try. ARGH!!!!! Then my sister sent me a link for a story about the teenage boy who committed suicide. This was several weeks before the Singulair/suicide stories were in the news. I did some research, and I started reading these posts. It was like I was reading descriptions of my son!! I talked to several pharmacists and none of them knew of any behavior problems attributed to taking Singulair. Talked to his pediatric pulmonary doc, he knew of no connection, but said to try taking him off. He thought the allergy/asthma would be OK since he also uses an inhaled steroid every day. Well........... I thought I could see a difference in 4 or 5 days, my husband thought I was wishful thinking! But, since then everyone in his life agrees, he is a different kid! No moodiness, no unexplained anger, more on task, sleeping better. I could go on and on. There is no doubt in my mind, the differences started when he stopped taking the Singulair.

My six year old son has been on Singulair since he was two. We have had problems with aggression, mood variations, and severe defiance to even the simplest requests. It came to my attention via a website on explosive kids that perhaps Singulair may be to blame. As I said I have no real prior behavior (he was only two) to compare this behavior to, however if it was the Singulair that causes my lovable son to act the way he does, I'm not sure if I should just feel relief that we can take him off or complete rage that this drug has caused us four years of hell.

Can anyone tell me how long it might take for me to notice a difference. He has been off for about a week, I think things seem different but perhaps it's only wishful thinking.