CNS Effects The most frequently occurring effect is initial drowsiness that generally subsides with continued usage of the drug or lowering of the dose. Noted less frequently were depression, hyperactivity and euphoria. Neurological Extrapyramidal Symptoms Extrapyramidal symptoms noted below may occur in susceptible individuals and are usually reversible with appropriate management. Akathisia Motor restlessness may occur early. Parkinson Syndrome Akinesia, characterized by rigidity, immobility and reduction of voluntary movements and tremor, have been observed. Occurrence is less frequent than akathisia. Dystonia Class effect: Symptoms of dystonia, prolonged abnormal contractions of muscle groups, may occur in susceptible individuals during the first few days of treatment.