January 2005 I had a work related medical, heart (EEG), blood pressure, cholesterol, gulcoses, weight perfect. Doctor mentioned I was very weezy in chest, I still smoked then as well, not anymore. I stated I was a mild hayfever & bronchical asthma sufferer, not on medication. Prescription Singulair. So I tried it!!! Initially I improved, my breathing, my reaction to different air temperatures, walking up hills, hayfever etc. March 2005 I went to the bathrm at 3am and fainted!!! I believe I was then misdiagnosised - maniac depressant, full of anxiety, even irregular levels of nervosis where detected in a brain electrodes analysis. Presciption Trazodone-antidepressant. Symptons persisted, dizziness, faintness, irregular energy levels, weight gain, bad moods, muscle tension in neck/shoulders, fear of life/social activity. I´ve stopped Singulair & in 10 days I feel a little back to normal. But I have a long way to go still, now I have to get off the antidepressants. Could all my suffering be related to Singulair????? My guest is, it is more than possible, especially after reading all the posted side effects - Merck & Sharp also produced it - look what suffering they caused with "VIOXX" - arthritic painkiller, even death!!