I started Bupropion 100 mg this past Monday after going off Cymbalta 60 am 60 pm last week. I feel terrible, light headed, shaking inside and outside. Dr decreased alprazolam .25 from 3 to 1 a day all at same time. I have back injury and am on oxycodone 5/325 up to 3 times a day and Nucynta 50 mg 2 times a day but after having a regular back procedure I decrease oxycodone down to 1 a day, then I decrease Nucynta to 1 a day. These decreases are done by me and have done this for a few years. Is problem probably coming from new script maybe or have I been dropping meds too fast.