I started on 12mg then onto 25mg the onto 75mg and that is where the trouble started. I felt like a zombie .,and although I was using them for back pain, I was getting no relief. So I asked my doctor to take me off them. I started on 75m for 5 days then 50mg for 5 days, and lastly 25mg for 5 days. I started feeling ill on the second day of the first reduction, but carried on until I got where I am now and that just having come off the 25 mg about 4 days ago, and I am feeling really unwell, Can't sleep. My body aches all over, I have dreadful nausea, headache, and during the night while I am awake all night trying to manage my pain, but the worse thing is the tension in my joints. It is driving me crazy. I'll never use fentanyl again as long as I live