Athetoid cerebral palsy is one of three types of cerebral palsy, and affects between ten and twenty percent of patients. This form of cerebral palsy is caused by damage to parts of the brain called the cerebellum or basal ganglia. These parts of the brain help maintain coordinated and smooth movements and overall body posture. People with athetoid cerebral palsy demonstrate uncontrollable, involuntary, slow, writhing movements of the limbs, and sometimes of the face or tongue. These movements tend to become worse during periods of stress, and disappear during sleep.

Patients may be unable to walk or stand because of poor muscle tone, and may also have difficulty grasping and holding on to objects. Their inability to coordinate movements may also make them unable to feed themselves and perform other activities of daily living. When the face and tongue are involved, patients with athetoid cerebral palsy may grimace, drool or thrust their tongues out. Tongue involvement may make them unable to swallow properly or to speak normally, a condition called dysatrhria.

Patients with athetoid cerebral palsy can be prescribed a group of drugs called anticholinergics to reduce abnormal movements. Such drugs block the action of acetylcholine, a compound in the body that acts on nerve cells to trigger muscle contraction. Some commonly prescribed anticholinergic drugs are trihexyphenidyl, benztropine and procyclidine. Speech therapy plays an important role in managing athetoid cerebral palsy, and can help normalize swallowing movements and reduce slurred speech. Nowadays, special computers and voice synthesizers are available to make speech clearer.

Athetoid cerebral palsy does not improve or become worse with age, but it is distressing for the large number of people with normal intelligence who have this condition. However, normal mental ability often motivates patients to work harder to reduce movement and speech deficits through therapy and to lead productive lives.