Very common (10% or more): Extrapyramidal disorder (up to 34%), hyperkinesia (up to 13%), headache (up to 12%)
Common (1% to 10%): Tardive dyskinesia, dystonia, dyskinesia, akathisia, bradykinesia, hypertonia, somnolence, masked facies, tremor, dizziness, parkinsonism/parkinsonian effects
Uncommon (% to 1%): Convulsion, akinesia, cogwheel rigidity, sedation, involuntary muscle contractions, gait disturbance, persistent tardive dyskinesia
Rare (% to %): Motor dysfunction, neuroleptic malignant syndrome, nystagmus
Frequency not reported: Drowsiness, epileptic/grand mal seizure, vertigo , lethargy
Postmarketing reports: Opisthotonos [ Ref ]
Hearing voices can be a symptom of serious, and even life-threatening, conditions. Seek immediate medical care (call 911) if you cannot distinguish the voices from reality or if the voices are accompanied by bluish coloration of the lips or fingernails; chest pain or pressure; cold, clammy or dry, hot skin; confusion or loss of consciousness for even a moment; high fever (higher than 101 degrees Fahrenheit); persistent vomiting ; rapid, slow or absent pulse; respiratory or breathing problems, such as rapid or slow breathing, shortness of breath , or no breathing; seizure ; serious injury; severe abdominal pain ; or threatening, irrational or suicidal behavior. Also seek immediate medical care if the voices you hear are telling you to harm yourself or others.