Introduction
Tardive Dyskinesia is a condition that effects the nervous system and results in symptoms such as – uncontrollable movements of the tongue, jaw, or lips writhing, twisting, dancing movements of fingers or toes rocking, jerking, flexing, or thrusting of trunk or hips.
Iatrogenic movement disorders caused due to a blockade of dopamine receptors.
Aetiology
TD is most common in schizophrenics and bipolar patients treated with antipsychotic medications, but they can occur in any patients.
First & second-generation neuroleptics/antipsychotics:
Typically, the first-generation antipsychotics with increased dopamine D2 receptor affinity are affiliated with a higher risk of causing permanent abnormal involuntary movements. Atypical antipsychotics have fewer extrapyramidal side effects compared to typical antipsychotics due to their lower affinity for dopamine D2 receptors in the dorsal striatum and concomitant blockade of serotonin 5-HT2A/2C receptors.
Other medications:
- Antidepressants
- Lithium
- Antiemetics
Clinical features
Tardive dyskinesia presents clinically as stereotypical involuntary movements of the tongue, neck and facial muscles, truncal musculature, and limbs.
- Buccolingual stereotypy: Characterized by lip-smacking, tongue protrusion, perioral movements, chewing movements or puffing of cheeks.
- Other abnormal movements: Akathisia, dystonia, myoclonus, chorea & tics
- Parkinsonian syndromes
Diagnosis
A diagnosis of antipsychotic-induced tardive dyskinesia is made after the symptoms have persisted for at least one month and required exposure to neuroleptics for at least three months.
Abnormal involuntary movement scale (AIMS):
It is recommended to administer the AIMS at baseline before initiating antipsychotic medications and then at least three months after that while on treatment. Upon evaluation of the patient, it can be noted that tardive dyskinesia is present at rest and somewhat diminished when there is any form of movement.
Management
Dopamine receptor antagonists should be avoided whenever possible by selecting other medications that have a lower potential to cause tardive dyskinesia. Furthermore, chronic use of first-generation antipsychotics should be avoided whenever possible.
Dopamine receptor antagonists:
- Clonazepam
- Ginkgo biloba
- Vesicular monoamine transport type 2 (VMAT2) inhibitors: Valbenazine, deutetrabenazine