Baclofen and Phenol
From Holoprosencephaly
Baclofen
Baclofen is used as a "muscle relaxant" to help decrease muscle tone in children and adults with spasticity from various causes, including HPE. It can be quite helpful for several reasons. If the child is uncomfortable from the high muscle tone for instance, it may help. Also, once muscle tone gets very high, it sometimes can be quite difficult to care for your child. For instance, if the muscle tone in the hips is too high, it could be difficult to open the child's legs to change the diaper. A reason not to use baclofen would be if the child is using the high muscle tone for some function. For example, some children will be able to stand because of the high muscle tone in their legs. Once you take this high tone away with baclofen, they can become more "floppy" and not be able to stand. The good news is, baclofen "wears off", so you can try it, and then stop using it if you're not happy with it. The most common side effect is sedation. For this reason, the dose is usually started off very small, and then increased slowly. This seems to decrease the chances of having this side effect. Also, the sedation is "dose related" meaning that if the child is sleepy at a certain dose, you can try a lower dose.
Phenol
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.
Source: Carter Centers for Brain Research in Holoprosencephaly and Related Malformations http://www.stanford.edu/group/hpe/support/FAQ.html#Q2
