Seizures and Singulair

Our 10 year old son has been on singulair for approx. 5 years for allergies and "mild asthma". About a month and a half ago he started having what I thought were tics, moving his eyes side to side, turning his head side to side and sometimes flicking his eyes diagonally upwards. He had no idea that he was doing this and was able to talk to me while it was happening.(Did this daily for three weeks)
I was able to tape one of these episodes and brought it to our GP who then sent us straight to an ER Pediatrician who then sent us directly to an opthamologist. 20/20 vision, but all the above docs think seizures. MRI came back fine, still waiting for EEG results.
Started doing reading about singulair and was shocked. Took him off singulair and 2 days later the seizures stopped. He has only had 1 episode (that I've witnessed) in the 3 weeks that he has been off singulair. Also noticed a change in his mood, happier, chattier, more willing to be active and participate.
Will keep you posted on EEG and ped. neurologist appt in 3 months.