Still not sure if i have IBS because it also feels like "anxiety belly". For instance, i quit gabapentin short term, and even though it's not an opiate, the the withdrawals were intense. Generally, people get anxious, spastic, emotional, etc. When i was going thru the withdrawals, i felt all that, but most importantly, this gripping belly pain. I thought this was IBS, but realized it was just gaba withdrawals that faded with time. I do take a low amount of painkillers, only about 2 pills a day. however, sometimes i wonder if i'm experiencing withdrawals from those since i go all night with no meds (sleeping). When i wake up, i have this feeling that is similar to anxiety, restlessness, and stomach cramps. The fact that it fades by the time i am up moving about (and usually around the time i take my morning meds) makes me wonder if it's med related. I have some evidence of this because for brief times, i was on a longer-acting painkiller, and it seemed like my stomach pain was less in the morning. So, could it be opiate withdrawal? i dont know. I dont want to be put back on long-acting painkillers because in my body, they lead to more tolerance/dependence since the med is in your system around the clock. I am able to avoid tolerance and stay on a low amount of meds by sticking with short acting meds. The fact that you feel good for a short time when you wake up, and then the pain kicks in, exactly mirrors what most pudendal patients go thru. It was the same thing with my bladder. I used to be confused about this, and i assumed it was all physical/muscular, but another doctor explained that when you sleep, your central nervous system goes into a meditative relaxed state. After you wake up, your nervous system is ramping back up again, and the pain appears. Having a good gap in the morning is a good indicator of Central Sensitization / TMS.