Tardive dyskinesia (TD) is a difficult-to-treat and often incurable form of dyskinesia, a disorder resulting in involuntary, repetitive body movements. In this form of dyskinesia, the involuntary movements are tardive, meaning they have a slow or belated onset. This neurological disorder, by definition, most frequently occurs as the result of long-term (usually at least 3 months duration) or high-dose use of antipsychotic drugs,[Note 1] or in children and infants as a side effect from usage of drugs for gastrointestinal disorders
Tardive dyskinesia is characterized by repetitive, involuntary movements. Some examples of these types of involuntary movements include:
Grimacing
Tongue movements
Lip smacking
Lip puckering
Pursing of the lips
Excessive eye blinkingRapid, involuntary movements of the limbs, torso, and fingers may also occur. In some cases, an individual’s legs can be so affected that walking becomes difficult or impossible. These symptoms are the opposite of patients who are diagnosed with Parkinson’s disease. Parkinson’s patients have difficulty moving, whereas tardive dyskinesia patients have difficulty not moving.
Respiratory irregularity, such as grunting and difficulty breathing, is another symptom associated with tardive dyskinesia, although studies have shown that the prevalence rate is relatively low