Not a chemical drug. Reduces pain signals going to brain and replaces it with a tingling sensation like a TENS unit. Has reduced my perceived pain considerably. Have been able to reduce quantity of pain medication taken. Works much better than a TENS unit because the TENS cannot go deep enough (for me at lest) to get to the area causing the pain. Much more convenient than TENS, no attaching electrodes, etc. Just need to charge the battery periodically. You charge a small device called a "puck". Then you either tape the puck on at the implanted battery site or wear it in a belt that places it over the site. Then the puck charges the battery through the skin, that's all there is to it. You have a wireless remote then to change your programs that the technician has set up to cover your problem areas.Cons
Haven't had any so far. As with any procedure there are some that can occur: lead migration, battery problems, built-up tolerance, infection, etc.