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Tardive Dystonia

Practice Essentials

Tardive dystonia is a form of tardive dyskinesia. It is a movement disorder characterized by involuntary muscle contractions caused primarily by taking dopamine receptor blockers like antipsychotic medications.

Signs and symptoms

Tardive dystonia starts insidiously and progresses over months or years, until it becomes static. Dystonia typically presents in a twisting pattern with deviations on multiple anatomical planes. The movements typical of tardive dystonia are generally slower and more sustained than other dyskinesias.

Symptoms of dystonia can range from very mild to severe. Dystonia can affect different body parts, and often the symptoms of dystonia progress through stages. Some early symptoms include:

a “dragging leg”

cramping of the foot

involuntary pulling of the neck

uncontrollable blinking

speech difficulties

See Clinical Presentation for more detail.

Diagnosis

There is no single test to confirm the diagnosis of dystonia. To differentiate tardive dystonia from all causes of dystonia, base the workup on the history findings and clinical presentation of the dystonic movements.

A routine evaluation may include the following:

Electrolyte levels

CBC count with peripheral smear

Thyroid hormone indices

Calcium level

Magnesium level

Liver enzyme values

Erythrocyte sedimentation rate

Antinuclear antibody level

VDRL test

HIV antibody titer

Serum, copper, and ceruloplasmin values

Electroencephalogram, CT scan, or MRI of the brain

See Workup for more detail.

Management

The first step after the diagnosis of tardive dystonia induced by neuroleptics or other drugs is to taper and then discontinue the causative drugs. Many times, a severe psychiatric illness makes this impossible, but carefully reconsidering the indications for dopamine antagonists in a given patient and considering alternate therapy are imperative. Switching these patients to antipsychotic medications, like clozapine, with less potent dopamine blockade may be considered.
Unfortunately, it is not uncommon for the symptoms to worsen for a time after the offending medication is discontinued or reduced.

A recently introduced treatment is botulinum toxin which is injected into the affected muscle. There it blocks the effect of the chemical acetylcholine that produces muscle contractions. Consider botulinum toxin therapy if the dystonia is focal and amenable to the treatment.

The primary pharmacological treatment for tardive dystonia is dopamine-depleting agents. Another option would be dopamine receptor blockers (ie, neuroleptics).
However, 2013 guidelines from the American Academy of Neurology do not recommend the use of risperidone because it appears to cause tardive symptoms.
Instead, amantadine and tetrabenazine are recommended. A common observation for all tardive syndromes is that the symptoms improve with an increase of dopamine blockade and worsen with a decrease. Thus, the goal is to add a medication that will provide dopamine blockade while minimizing the risk of worsening the tardive syndrome or creating new tardive syndromes.

Deep brain stimulation is probably the surgical treatment of choice at this time for those with severely disabling dystonia who have not responded to medical therapy.

See Treatment and Medication for more detail.

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