Injectable antispasmodic medications for cerebral palsy

Examples

How It Works

Injectable medications, like other antispasmodic medications, relax muscles and reduce muscle spasticity. They act only on the nerves and muscles surrounding the area where they are injected. Health professionals give the injections directly into the affected muscle.

Why It Is Used

Injectable medications help relax tight muscles in the legs or arms affected by cerebral palsy. Injectable medications may be used:

• When muscle tightness interferes with daily activities, especially walking.
• To increase the effectiveness of physical therapy.
• To determine whether nerve surgery is appropriate. Doctors often can predict the potential success of surgery by how nerves and muscles react to the injected medication.

How Well It Works

These medications may improve the effectiveness of physical therapy or delay the need for surgery on the muscles, tendons, and joints. If injectable medications successfully relax the nerves and muscles, surgical cutting of the nerves may also be helpful. However, the overall usefulness and safety of these medications as treatment for cerebral palsy need more research.

Botulinum toxin (Botox) has been shown to improve the two main factors of leg spasticity: walking foot pattern and ankle position.¹ However, further research is needed on its short-term and long-term effects on leg spasticity in children with cerebral palsy.²

An injectable treatment usually relaxes tight muscles for a limited time. Alcohol and phenol start to work right away and last about 3 to 6 months. Botox usually begins to take effect within 3 days after injection, although the full effects are frequently not evident for 1 to 2 weeks. The effects of Botox last for about 4 to 8 months.

Side Effects

The side effects of alcohol and phenol injections include:³

• Pain as the injection is given.
• Muscle stiffness (rarely can become permanent).
• Loss of feeling in area, sometimes lasting for several weeks.

The side effects of Botox include:

• Pain at the site of the injection.
• Rash.
• Flu-like symptoms, such as nausea.

In rare cases, Botox use is related to severe side effects, such as trouble breathing or swallowing. They can occur as early as one day and as late as several weeks after treatment. Call your doctor right away if you or your child has muscle weakness, trouble breathing, or unexpected or increased trouble swallowing or talking.

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

What To Think About

Using injectable medications helps loosen tight muscles and joints and may prevent the need for braces, casts, or splints. If injectable medications relax nerves and muscles, surgery may be postponed or canceled.

Botulinum toxin (Botox) may be more useful than antispasmodic pills for treating cerebral palsy.

Using botulinum toxins to treat severe arm and leg muscle spasms (limb spasticity) in children or adults is an unlabeled use. More research is needed about the safety, dosage, and success of botulinum toxins in treating people who have cerebral palsy and for use in any condition in children younger than age 12.

Drowsiness, often caused by medications taken by mouth to relax tight muscles and reduce muscle spasms, is not a problem with injectable medications.

Both alcohol and phenol can be injected directly into the nerve that supplies a muscle. This is called a nerve block or a motor point block.

Injectable botulinum toxin goes directly into a muscle.

Botulinum toxin is easier to give and causes less muscle pain than the other injectable medications. But botulinum toxin costs more than alcohol or phenol.

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