Check her allergy meds. Seriously, they can have this effect. MY DS was a moody irritated mess on Zyrtec (my friend just happened to mention he was acting like her child when he was on Zyrtec and I looked at the side efftcts and it is actually a listed side effect). There is another med that is notorious for causing quite severe behavioral problems... I forget the name of it but my niece is on it. I decline to have DS try it because the behavioral stuff was just too risky. I'll text my brother and find out what the name is and post back.
Singulair (monolukast sodium) is what you are thinking of.
It works really well for a lot of people but does cause issues with some kids. I was aware of the side effects before we started using it, it worked well for DC for a while with no behavior issues. Then we had to switch to a different generic (insurance issues), and then there were behavior issues so we discontinued and asked the doctor for other choices. There are a lot of choices for allergy and asthma meds and it really all depends on the person which one will work with the least side effects.
