Tardive dyskinesia is characterized by repetitive, involuntary, purposeless movements. Features of the disorder may include grimacing, tongue protrusion, lip smacking, puckering and pursing of the lips, and rapid eye blinking. Rapid movements of the extremities may also occur. Impaired movements of the fingers may also appear. For comparison, patients with Parkinson's disease have difficulty moving, while patients with tardive dyskinesia have difficulty not moving.

Other closely related neurological disorders have been recognized as variants of tardive dyskinesia. Tardive dystonia is similar to standard dystonia but permanent. Tardive akathisia involves painful feelings of inner tension and anxiety and a compulsive drive to move the body. In the extreme, the individual undergoes internal torture and can no longer sit still. Tardive tourettism is a tic disorder that can closely mimic Tourette Syndrome, sometimes to the point where the two can only be distinguished by the details of their onsets. Tardive myoclonus, a rare disorder, presents as brief jerks of muscles in the face, neck, trunk, and extremities.