Singulair and Trichotillomania link?

My 10 year old son has been on Singulair for about a year. About 3 months ago he started pulling out his eyelashes, then his eyebrows. I He looks awful and his self esteem is taking a big dive. I've read a lot about trichotillomania and how it is classified as an OCD. New research is saying it may be tied to a genetic mutation, but now I'm wondering if there is a link with Singulair. He cries a lot more than usual lately and is expressing his unhappiness with his life. After reading these posts, my husband and I have decided to try and take him off the Singular for a while to see if anything changes. Has anyone else experienced the hair pulling while taking Singular? Thanks.