Singulair and persistent cough

My eight year old son was diagnosed with mild asthma by our GP and was taking Ventolin for a persistent cough. When this didn't relieve the cough the doctor prescribed Singulair. He started the Singulair in March 2009 and within 2 months we realized that his personality had dramatically changed. It has taken us a while to figure out what was going on because eight year old boys are starting to assert themselves more and I think the side effects have been escalating over the last month. He was angry most of the time, very hateful towards his siblings, saying very dark, nasty, hurtful things. He argued every time we asked him to do something and would snap into a screaming inconsolable emotional wreck at the drop of a hat many times a day over trivial or imagined problems. He was having nightmares and bursts of hyperactivity that were overwhelming. He told us he felt frustrated all the time and hated everything. When we tried to calm him he was unreachable. Just yesterday he had his fist clenched and pulled back ready to punch me when I was trying to help him with a computer problem. He was shaking and his face was contorted with rage and he just wasn't my little boy anymore.
It has been devastating for our family and we were ready to take him to a psychologist. He is normally an incredibly considerate, perceptive, loving child, highly intelligent, helpful and fun loving with a great sense of humor.
He has also complained of leg pains and has been wetting the bed again. It was only yesterday that I began reading about other people's side effects and have taken him off Singulair as of last night. Whilst he has still been argumentative today already the aggressive intensity seems to be easing.
I am absolutely mortified that I allowed this to happen to my son and my family and I am so grateful to others for sharing their experiences.
We still need to address his asthma and will make an appointment with a specialist next week, but given his asthma is so mild he should not have ever had to suffer these side effects.
I only hope now that he has not sustained any long term effects and that his younger brother has not been scarred by the truly horrible things that my son has said to him.

My son is 5 years old. He was put on Singulair in August following a case of pnemonia. He has asthma. I found it worked well since I was barely using inhalers anymore. His eczema was even getting better. So I was happy with the medication. He also seemed to be getting more agitated with us. At least three times a day he would have an outburst towards his brother or us, like he was going to punch or hit us. Then I would say "why are you mad at me" and he would say "I'm not mad, I'm frustrated" and then burst in tears. He was getting a lot of time outs. Then two months ago he started saying "this is not a good day" or "this is a sad day". I was wondering if singulair was to blame, but it wasn't until I heard concerns from other moms. I took him off it as an experiment and noticed the next day was without his outbursts. Then I just never gave him anymore...and I am relieved to say he is as "normal" as I remember him before Singulair!!! He also was unable to get to sleep easily on Singulair, sometimes 1, 2 and even three hours to get to sleep. Now he is out in 20 minutes if not less. I haven't talked to the Doctor yet. I have noticed his eczema is flaring up again and he has used his inhaler this week (although he has a cold). I think I can deal with that without Singulair and the problems I am suspicious come from it's use.

My 5 year old has been taking this for 2 months. He was having trouble with a persistent cough/runny nose, which the dr. diagnosed as allergies. Since starting Singulair, he has had a marked changed in his personality. He has become aggressive, angry, and depressed, and started hitting himself. It is as if he doesn't know how to deal with his emotions. This is very unusual behavior for him, he is normally a very happy, laid back, loving child. I am relieved to find this website & see that other parents have gone through this same experience, it has been helpful information. I have a call into the dr. office now to get a different medication, or else take him off it completely. Thank you for the help.