These are numbing medicines similar to the one the dentists use to freeze the teeth. These injections serve at least 2 purposes. One, for the diagnosis – to identify the structures involved in producing the pain. Second, for the treatment – although the length of action of these medicines is only few hours, often the effect outlasts the duration of action. For example, following trigger point injections and nerve blocks, the pain relief often lasts longer than the anticipated period of drug action.
Steroids have anti-inflammatory property. Inflammation is tissue response to irritation. By reducing the inflammation the medicine can reduce the pain. Steroids can also calm down the activity of the nerves which is helpful in some pain conditions. A common concern among the patients is the possibility of the steroids causing side-effects in the rest of the body such as leading to obesity. The injected medicine is intended to act locally. When limited to the recommended dose and if the injections are not repeated very frequently it is generally safe to use these medicines in managing pain.
Commonly used in cosmetic procedures in face to appear pretty! Botox can relax the muscles. In muscle pain the medicine is used to relax the muscle and reduce the pain. There is also evidence that apart from relaxing the muscles botox can also inhibit the release of certain chemical substances that cause pain.
Phenol / Alcohol These are medicines which cause permanent destruction of nerves. The medicines are used in managing cancer related pain and less frequently in some persistent intractable pain conditions. Although careful injection can produce long-lasting pain relief, the nerves can grow back and there are reports that the pain can come back with vengeance. In selective cases it has useful role.
Radiofrequency lesioning Radiofrequency (RF) therapy uses a needle (electrode) to conduct current that destroys tissue with high temperatures (about 80° C) or charged particles. In pain management, the goal of RF therapy is to selectively destroy nerve tissue to stop pain signals. Several studies have demonstrated near total relief of pain is possible with a meticulous approach to electrode placement close to the nerve.
Pulsed Radiofrequency lesioning The concept of pulsed RF is to block pain without causing destruction or damage to the nerves. The nerve is stunned by an intermittent electrical current from a special machine. Although this is a relatively novel technique, there are growing evidences that this intervention may help to treat pain in patients when they fail to respond to conventional therapies.