of Dysthymia , Neuropathic and Chronic Pain , Somatoform Pain Disorder , Migraines , Chronic Tinnitus , Panic Disorder and General Anxiety Disorder . Typical side effects include nausea , profuse sweating , headaches , Xerostomia , narcolepsy or insomnia , constipation or diarrhoea and blurry vision . More unusually, it can