Can phenol block be used for muscle tightness and spasticity?
Phenol (carbolic acid) creates a chemical nerve block. It is used in adult medicine to treat localized problems of spasticity (high tone or tightness) without the side effects of such anti-spacticity medications taken by mouth as diazepam (Valium). Phenol is an agent that injures the local nerve it has been injected close to. It is important that the injection be close to the nerve of interest. This usually requires electrical studies to locate the nerve and this is painful and difficult for young children to tolerate. It is sometimes done however in children under sedation or general anesthesia. It is important to note that the “block” is really a reversible injury to the nerve. The effects are highly variable and usually last 3-6 months. Side effects of these blocks are usually limited to local discomfort or bruising, but occasionally pain of a more significant nature is seen.
