Singulair Side Effects: I have been on Singulair for about 6 weeks, the first 3 weeks I http://www.medications.com/effect/view/31975 I have been on Singulair for about 6 weeks, the first 3 weeks I had a headache all the time, but that finally past. Now my joints hurt all the time, could this be form the singulair Yes, there are a lot of people on this site that have had the sam Tue, 01 Jul 2008 19:39:27 -0400 http://www.medications.com/effect/view/31975?item=9699 Yes, there are a lot of people on this site that have had the same problem. http://www.medications.com/effect/view/31975?item=9699