Actually falling asleep. Narcotics knock you out in high dosages, so you get used to taking a nap after every dose. Then, when you aren't taking them, your body has trouble triggering sleep. I would have to either have a few drinks or smoke some weed to get drowsy enough to sleep. Once I was over the initial withdrawal period I was able to resume natural sleep cycles. I also started using various herbal products to help with the chronic aches and the remaining inflammation, I believe these helped as well.