Thanks for your question. There are both prescription drugs and non-prescription drugs which help in controlling chronic pains. All medicines have side effects and should be taken according to the prescription of doctor. Some medicines may take weeks to start reducing pain. It is better to talk with your doctor if you are experiencing any dangerous drug interactions. For treating chronic pain, commonly used medicines are NSAIDS (Advil, Aspirin, Motrin), Serotonin-neopinephrine inhibitors, pain relievers which are applied to skin like Lidoderm, fentanyl, capsacin, opiate pain relievers like vicodin, oxytocin etc. Trigger point injections, epidural steroids, nerve block injections etc. are also used to treat chronic pains. Anyway, it is recommended to follow up with some specialist about your problem, especially gastroperisis. Good luck.