My 5 year old has been taking this for 2 months. He was having t...

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.