Singulair and self doubt

My son is 8 and for the past 3 years has been on Singular for seasonal allergies. He has since been diagnose with asthma and he takes Singular daily. After being on it for 3 weeks he is now getting into trouble in school. The teachers say it was like a light switch being turned on. Completely out of character behavior. My question is this......has anyone experienced hyperactivity behavior on Singular?

UPDATE:It is now a week since my 6 yr old son stopped taking singulair. My happy boy is back! He has now had a second day in a row with positive reports from school. These are the first 2 positive days of the entire school year!!! Its no mystery anymore! I am 100% positive it was the Singulair he was on. It may work for some people with no side effects and thats great for them. But for those parents out there that had the slightest doubt I am telling you from experience to go with your gut! Speak to your Dr for alternatives and get back your happy children!

I have a 8 year old daughter that has been on Singulair since she was 2 years old. When she first started Singulair, she was also put on Flovent (an inhaled steroid), along with Albuterol for what the doctors call reactive airway disease (similar to asthma). Her triggers were allergies and having a cold. Her first flare up of mood swings alerted me to take my daughter off the Flovent. She seemed to improve a little, but still had behavior/moody issues. I had chalked them up to the "terrible twos", and not really thought much of it. As time went on, I became accustomed to the behavior that my daughter was showing. When the few complaints of stomach pains, headaches, and leg pain came along, I managed to explain them away with reasonable explanations (example: growing pains, eating too much, not enough sleep, etc.). As my daughter went off to school, I heard numerous complaints from her teachers that she lacks focus, cannot complete a task in a timely manner, easily gets distracted, and at times (more than not) is a disruption to the class. At home, I noticed a strange "tick" going on with her blinking, the constant need to repeat herself, and the battles with bursts of crying to get her to do ANYTHING. SOMETHING IS REALLY WRONG!!! I was on the edge of having a full work-up of mental tests. I have her see the school social worker weekly and I keep a constant communication with her teacher regarding her behavior. I decided to look up side effects regarding this medication. I first looked at the website for the manufacturer and saw nothing alarming, nothing about behavior affected side effects. I looked into mental disabilities (autism, aspergers, ADD, ADHD, etc.) and saw no common link to her behavior. Then I came to this site and MY JAW DROPPED!! Everything that my daughter has experienced, TO THE LETTER, has been experienced by other children. The weight gain, the occasional pains, the strange behavior. I decided that NOW is the time to act. I have seen my daughter's doctor and discussed my concerns. We are going to wean her off this stuff starting TODAY! Fear of a serious relapse of breathing problems is making us very cautious. I am kicking myself for not making the connection sooner. Wish us luck that this drug has not destroyed her chances of getting better and that this "asthma" can be controlled another way without such serious side effects.