Antispasmodics (muscle relaxants)

Antispasmodic medications relax muscles and reduce muscle spasms. Specifically, diazepam relaxes the brain and body, baclofen blocks signals between the spinal cord and the muscles, and dantrolene interferes with muscle contraction.
Why It Is Used

Antispasmodics are used before physical therapy for cerebral palsy or at bedtime to help relax tight muscles and stop muscle spasms. Diazepam (such as Valium) helps relax muscles after orthopedic surgery.
How Well It Works

Although antispasmodics can help relax muscles temporarily, they have not been proved to improve general muscular function. Diazepam (Valium) may be of some use in people with CP whose emotional stress contributes to their spasms or abnormal movements.
Side Effects

The most common side effects of oral antispasmodics include:

    * Drowsiness.
    * Weakness.
    * Nausea.
    * Skin rash.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)
What To Think About

These medications may become ineffective when used over long periods.

Children taking these medications may have difficulty paying attention in school. The long-term effects of oral antispasmodics on children have not been studied enough to guarantee safety.

Dantrolene sodium (Dantrium) may cause liver damage. Frequent blood tests are needed to check liver functioning when a person is taking this medication.

Diazepam (such as Valium) cannot be used in people who have glaucoma.

Baclofen (Lioresal) may also be given directly into the fluid surrounding the spinal cord (intrathecal baclofen). A small pump is placed under the skin of the abdomen. Medication is carried through a tube attached to the pump into the fluid surrounding the spinal cord. The pump is programmed to release a continuous amount of medication. So far, the benefits of giving baclofen this way include:

    * Reduced medication needs. Because intrathecal baclofen is given right into the spinal fluid, it takes less medicine to be effective than pills. This reduces side effects such as nausea and drowsiness, which are a problem with the oral form of the medication.
    * Improved muscle strength, tone, and function.

Disadvantages of using baclofen through a pump include the following:

    * Surgery is needed to place the pump under the skin in the abdomen.
    * The pump and surgery are expensive.
    * After the pump is inserted, it needs to be filled with medication regularly every 2 to 3 months.
    * The insertion of the pump carries a risk of infection.
    * On rare occasions, problems with the pump, such as failure or breakage, result in sudden withdrawal. Symptoms such as itching, rebound spasticity, and rapid heart beat may be noticed. Other malfunctions can cause an overdose and lead to breathing problems and coma.