Cerebral palsy (CP) is experienced in different ways for each child diagnosed, but muscle issues are generally a common symptom of all children with the disorder. Muscles are often too stiff or move in spastic ways. They can become rigid or move in a way that is uncoordinated. The stiffness, rigidity, and spasms that many children and adults with CP experience are disruptive, uncomfortable, and even painful, or interfere with swallowing and breathing.
Medication use is just one line of treatment for CP, and typically targets symptoms in an attempt to control them as a cure with drugs is not possible. One category of medication that can help relieve the pain, stiffness, and spastic muscle movements that are characteristic of CP includes various muscle relaxants. Taking medications is always a balance between risks and benefits and those with CP, or their parents must decide if muscle relaxants help enough to outweigh any side effects of risks.
Cerebral Palsy and Muscles
Cerebral palsy is a disorder of movement and muscles. It is related to nerve and brain damage. When these parts of the body are damaged it affects the muscles and therefore how a person moves. The severity of this effect varies by an individual with some unable even to walk while others simply struggle with balance.
The most common type of CP is spastic, which means that muscle tone is increased compared to someone without the condition. The increased tone makes the muscles stiff and rigid, and as a result, movements are spastic. The spasms may affect one whole side of the body, mostly the legs, or in severe cases all parts of the body, including the face and throat.
Less common types of CP affect balance, control of movements, and even the ability to swallow or talk. In some cases, the muscle tone of an individual can vary from too loose to too tight. This is called dyskinetic CP. Other patients with the condition have varying symptoms that can’t be categorized as one type or another. Nearly all CP patients experience rigid and spastic muscles at least some of the time.
Consequences of Spastic Muscles
Having overly toned muscles resulting in spasms and rigidity is uncomfortable and can even be very painful. It can also place limitations on a person with CP and be embarrassing, especially for older children, teens, and adults. Spasms can interfere with other types of treatment, like physical therapy and can prevent a person from being able to sleep at night. Controlling spasms and relaxing rigid muscles is an important part of treatment for CP.
One strategy for treating spastic muscles and tight muscles is to use medications. Muscle relaxants, also known as antispasmodics, are drugs that decrease muscle tone by acting on the central nervous system. The result is less stiffness, rigidity and smoother, less spastic movements of muscles. The effects are temporary, so patients with CP cannot get permanent relief from these medications.
Muscle relaxants may also cause side effects, which may bother some people more than others. If the side effects are too uncomfortable, different types of muscle relaxants can be tried or they can be used only when spasms are most severe or interfere with sleep and other important functions. The main side effect of most types of muscle relaxants is sedation. In addition to relaxing muscles, they tend to relax the brain and operating machinery while on these drugs is discouraged. They may also cause skin rashes, nausea, and weakness.
Baclofen is one type of muscle relaxant that can be prescribed for children or adults with CP. Brand names for this drug include Gablofen and Lioresal. It is thought to reduce spasticity by blocking signals that run from the spinal cord to muscles. It can be dosed orally or injected directly into the spine. The latter method is newer and delivers the medication directly to the location where it is needed.
To be given baclofen directly in the spinal fluid requires having a small device implanted under the skin. This has been approved for children with CP and requires a few days in the hospital. Baclofen can cause fatigue, weakness, dizziness, nausea, and sedation and may also elevate liver enzymes.
Dantrolene, which is sold under the brand names Dantrium and Revonto, acts as a muscle relaxant by interfering with how muscles contract. It has been shown to be as effective, or more so for children with CP than diazepam, and is often better tolerated. Side effects include weakness, malaise, diarrhea, and drowsiness, but the most serious potential side effect is toxicity to the liver. This can be irreversible, so must be carefully considered before using dantrolene.
Diazepam, also known as Valium, is a benzodiazepine, a type of drug that has the potential for abuse and dependence. It can trigger a withdrawal symptom if use is abruptly stopped. Diazepam works by relaxing the brain and the body by acting on neurotransmitters in the brain. Common side effects are depression, sedation, and cognitive difficulties.
One study that investigated the use of diazepam in children found that when given one dose before bedtime, most children saw positive benefits and minimal negative outcomes. The medication helped their muscles relax so they could engage in therapeutic stretching before bed. The effects of the stretching lasted into the following day and there was no sedation reported after waking up the next day.
Other Muscle Relaxants
Other types of muscle relaxants that are used less often for CP include tizanidine. It may cause liver damage and cannot be used with blood pressure medicines. It may cause dizziness, drowsiness, and dry mouth. Flexeril is another less common muscle relaxant for CP. It is indicated for muscle spasms and may cause drowsiness, nausea, stomach upset, dizziness, diarrhea or constipation.
Muscle relaxants used to treat CP can be useful and for many patients provide much-needed relief from pain and discomfort. On the other hand, they come with some risks and can cause sedation and other side effects that are hard to live with when trying to perform daily functions. As research progresses, there may be more medications on the horizon that can help these patients feel better with fewer side effects.