Spasticity and Drug Therapy for Cerebral Palsy

One of the major characteristics of cerebral palsy is spasticity, meaning that the muscles are stiff or rigid muscles. It also describes stiff, rigid muscles interfering with normal muscle activity, movement, walking or speaking. If muscles or tendons remain tense for too long, joints become bent in a fixed rigid position called a contracture.

Spasticity is caused by damage to the portion of the brain that controls voluntary movements. The motor area of the brain is found in the cerebral cortex. If this portion of the brain is damaged, it can affect how nerve impulses from the brain are carried along the spinal cord and through the nervous system to the muscles and tendons. These interrupted or abnormal messages can cause hyperactive deep tendon reflexes, causing knees to jerk, legs to scissor (open and close like a pair of scissors), and repetitive, or jerky motions.

Interrupted or irregular nerve impulses can also cause individuals with diseases like cerebral palsy, or with brain injuries, to hold their shoulders, arms or fingers in odd ways. Spasticity can be extremely debilitating and painful. It is also common in brain injured individuals. Common treatments for spasticity include physical therapy, medications and surgery.

Drugs are sometimes used to control spasticity, particularly following surgery. The three medications that are used most often are diazepam, which acts as a general relaxant of the brain and body; baclofen, which blocks signals sent from the spinal cord to contract the muscles; and dantrolene, which interferes with the process of muscle contraction. Given by mouth, these drugs can reduce spasticity for short periods, but their value for long-term control of spasticity has not been clearly demonstrated. They may also trigger significant side effects, such as drowsiness, and their long-term effects on the developing nervous system are largely unknown.

Patients with athetoid cerebral palsy may sometimes be given drugs that help reduce abnormal movements. Most often, the prescribed drug belongs to a group of chemicals called anti-cholinergics that work by reducing the activity of acetylcholine. Acetylcholine is a chemical messenger that helps some brain cells communicate and that triggers muscle contraction. Anticholinergic drugs include trihexyphenidyl, benztropine, and procyclidine hydrochloride.

Occasionally alcohol "washes" -- or injections of alcohol into a muscle Ç are used to reduce spasticity for a short period. This technique is most often used when physicians want to correct a developing contracture. Injecting alcohol into a muscle that is too short weakens the muscle for several weeks and gives time to work on lengthening the muscle through bracing, therapy, or casts. In some cases, if the contracture is detected early enough, this technique may avert the need for surgery.

Dantrium (Dantrolene)

What is Dantrolene?

Dantrolene, or Dantrium, is a muscle relaxant that works by blocking the muscles' ability to contract. It is prescribed to treat muscle spasms caused by cerebral palsy, spinal cord injuries and multiple sclerosis. It is also used to treat malignant hyperthermia, a rise in body temperature caused by anesthesia.

How is it given?

Dantrolene is given most frequently in oral form, however other methods may be used in operating room settings.

How can it help?

Dantrolene can help relieve severe muscle spasms and bring pain relief and increased movement.

What are the side effects?

Dantrium may cause serious liver damage and disease, including hepatitis and jaundice. Liver function testing should be performed before starting this medication. The most common side effects include diarrhea, dizziness, drowsiness, fatigue, vague feeling of illness, and weakness. Drinking alcohol while on Dantrium can increase symptoms of drowsiness and dizziness. Also, taking this drug with other medications, like antidepressants, antihistamines, sedatives and tranquilizers can be dangerous. Dantrolene has not been approved for use in children under age 5, and is not approved for use by pregnant women

Drug Therapy

Further information on Drug Therapy

Spasms and Drug Therapy