Abstract
As a serotonin-dopamine antagonist, risperidone is less likely than traditional antipsychotics to result in tardive dyskinesia (TD). There are not many reports of risperidone abruption-induced TD. Herein we report a new case of tardive dyskinesia induced by a sudden stop of risperidone during the treatment of an autistic patient with attention deficit hyperactivity disorder (ADHD) on risperidone. He was presented to the emergency department in King Fahd Central Hospital in Jazan, Saudi Arabia, with a history of abnormal movement in the form of unsteady gait, axial dystonia, twisting and spreading of fingers, shoulder shrugging, and protruding tongue associated with hypersalivation, with no other signs and symptoms. These symptoms started after two days of abruption. The laboratory and imaging results showed normal findings. Other causes that induced symptoms were ruled out. The diagnoses of tardive dyskinesia were presumed. Risperidone was not restarted, and clonazepam was started with a gradual increase of the dose from 0.2 mg/twice a day for five days to 0.2 mg/three times a day. The patient's symptoms improved, and he was discharged with a follow-up with a psychiatrist and neurologist. Risperidone and other atypical second-generation antipsychotics were used to treat autism spectrum disorders. TD is more likely to be triggered by the abrupt withdrawal of risperidone. The chosen laboratory tests and imaging tests are helpful in ruling out other causes that induce similar symptoms and presumed diagnosis of TD. The conventional recommended treatment for TD was clonazepam.