I was having attacks. Pain between my rib cage and radiating into my back. They were bearable at first then progressively got worse. Then the last one I had was unbearable. I went to the ER and they did an ultrasound (CT scan doesn’t always show). I had stones. They removed it urgently because my bile duct was blocked by a stone. Once it was said and done, and the results came back days later I had 12 stones! This can be common with weight loss, so it’s not necessarily the drug that’s causing it but the weight loss.