- Tardive Dyskinesia (TD) : - Tardive Dyskinesia (TD) : Tardive Dyskinesia or TD refers to a disorder that sometimes develops as a side effect of long-term treatment with neuroleptic (antipsychotic) medications. It is a neurological disorder consisting of abnormal, involuntary body movements caused by certain medicines. It is usually associated with long-term use of medicines for treating schizophrenia and other psychotic disorders. It is characterized by abnormal involuntary movements of the patient's face, mouth, trunk, or limbs