Hi Contract and welcome.
I'm sorry for your pain. Your question really is a hard one - have you discussed this with your doctor? As you are writing on a chronic pain forum, I'm guessing that you're needing a breakthrough pain medication?
What exactly is the cause of your? What sort of maintenance meds are you on? Do non-pharmacological measures help? E.g. heat/cold packs, massage, TENS?
Take care, and look forward to getting to know you
Laura