"i have been on butrans patch for about 6 months. started on 5mg, then 10mg after a few months, and then 20mg. i had several side effects although it did relieve my pain. just the past two days i had to go off of the patch because my side effects were very worse with being on the 20mg. the side effects i have experience since i started butrans 6 months ago are: in the beginning, very itchy all over, not just at the patch placement site..that did go away after about 3 weeks. severe horrible constipation...i mean horrible.. severe appetite loss. although i needed to lose the 27 pounds that i have lost since taking butrans, i am a worry wart, so i worry it could be something more severe, but i think its the patch. severe nausea too."