Examples
| Generic Name | Brand Name |
|---|
| alcohol "washes" | |
| botulinum toxin | Botox |
| phenol "washes" | |
How It Works
Injectable medicines, like other
antispasmodic medicines, relax muscles and reduce muscle
spasticity. They act only on the nerves and muscles
surrounding the area where they are injected. Doctors give the injections
directly into the affected muscle.
Why It Is Used
Injectable medicines help relax tight
muscles in the legs or arms affected by
cerebral palsy. Injectable medicines 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 medicine.
How Well It Works
These medicines may improve the
effectiveness of physical therapy or delay the need for surgery on the muscles,
tendons, and joints. If injectable medicines successfully relax the nerves and
muscles, surgical cutting of the nerves may also be helpful. But the overall
usefulness and safety of these medicines 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 But more research is needed on its
short-term and long-term effects on leg spasticity in children with cerebral
palsy.2
In most cases, an injectable
treatment 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 often 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 medicines helps
loosen tight muscles and joints and may prevent the need for braces, casts, or
splints. If injectable medicines relax nerves and muscles, surgery may be
postponed or canceled.
Drowsiness, often caused by medicines taken
by mouth to relax tight muscles and reduce muscle spasms, is not a problem with
injectable medicines.
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.
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.
Botulinum toxin is easier to give and causes less muscle
pain than the other injectable medicines. But botulinum toxin costs more than
alcohol or phenol.
Complete the new medication information form (PDF)
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