I have been taking Singulair since January 2003. It really helped my exercise induced asthma. In the summer of 2004, I had a tooth pulled and a bridge put in. My teeth and jaws started hurting and the dentist couldn't figure out any reason why they were. In the summer of 2005, while still on the Singulair, my left arm and neck started hurting leading me to believe I may be having heart problems. I had my heart checked out, and everything looked good. Last summer, still taking Singulair, I began having trouble swallowing pills. I finally stopped taking the Singulair the first of October 2006, and my teeth and jaws quit hurting; my left arm and neck quit hurting; and I don't have any trouble swallowing pills. I did get a nasty head cold a couple of months after stopping the Singulair and another one a couple of months later. I am wondering if those head colds may be associated with the Singulair as it has been many years since I have had a head cold.