In milder cases, the individual may complain of a sensation of inner restlessness and be unable to sit quietly without fidgeting . In more severe cases, the individual may actually be unable to remain seated and must pace or march around the room. Their sense of anxiety increases if they are unable to move about. While the above tardive syndromes are characterized by excessive movements, individuals may also experience a drug-induced parkinsonism which appears clinically like Parkinson's disease. With drug-induced parkinsonism, there is an absence of movement.
Individuals have slow movements with rigid or stiff muscles and tremor.
When walking, a shuffling gait is present with a stooped posture and diminished arm swing. Facial expression is blunted causing a very solemn appearance. Of all the tardive syndromes, drug-induced parkinsonism is the most reversible. It resolves after the medication is stopped, but this may take up to 18 months. The criteria for diagnosing a tardive syndrome can vary but is generally agreed to be exposure of an individual to a dopamine receptor blocking agent within 6 months of onset of symptoms which persist at least 1 month after stopping the offending drug.