Singulair

Has anyone noticed odd, but subtle, psychological effects from this asthma/allergy medication? It seemed to give me unusually strange dreams the first couple weeks I took it. Also, before falling asleep I was having a lot of flashbacks to things I hadn't thought about for a while, including past dreams. (Not that that sort of thing never happens while I am falling asleep, but when I started taking singulair, it started happening more often, though I guess that's faded away now.) Almost seems to have a mood-enhancing effect, even though it also appears to be making me a little drowsier than usual.