I cant believe I have found this site. My Girlfriend was diagnosed with Adult onset asthma a year ago after having a severe asthma attack. The hospital prescribed Singulair and symbicot inhaler. About two weeks into taking the Singulair I noticed her personality started to change. She became moody and agressive and started to talk of "mad" dreams. I then noticed her memory started to fail her and she could not find her words. She developed a rash and hives from time to time, and on occasions would talk sentences that did not make any sence. I would be very concerned that children would be given this drug as I am shocked to read others have had several experiences similar to ours. I am glad she has now stopped taking the drug and am looking forward to getting back my girlfriend.