I just found this site and I decided to respond. I have been taking Singulair on and off for about 5 or 6 years. When I first started taking it, it seemed to help my asthma quite a bit. I didn't notice any side effects, but then again I was taking a few other meds that I thought might be a culprit. I hadn't taken the Singulair for about 6 or 8 months because everything was going good. About 2 months ago I began having a few flare ups, so I thought I would go back on the Singulair. Now I am 57 y/o and been on most of my meds for about 10 years or so. When I added in the 10 mg dose of Singulair before bedtime, I began to notice dramatic side effects. Along with the more vivid dreams, in the first few days I noticed when I awoke I was real tired. Now that is unusual because I have always been an early riser and ready to go. Some days I felt like I didn't want to get out of bed. As the days went by, I noticed that I was waking up a lot at night and had a constant "hissing" noise in my ears. The noise would last thru the first few hours of the day and subside. In the last week or so, I began to awake with horrible headaches. The headaches started in the back of my neck and migrated to the top front of my head. I am not a headache person, so these are very unusual.
I have also noticed small painful bumps on my scalp. There has been a noticable thinning of my hair as well. I'm not sure if it can be attributed to the Singulair or just being old!
I will be going off the Singulair as of today to see if all these symptoms disappear. I will post a response in a week or so.