- Extrapyramidal disturbances are the major dose-limiting side effects with high potency antipsychotics like fluphenazine, haloperidol, pimozide, etc. - The extrapyramidal effects may be categorized into: Parkinsonism Acute muscular dystonias Akathisia Malignant neuroleptic syndrome Tardive dyskinesia - Parkinsonism usually appears between 1-4 weeks of therapy and it persists untill dose is reduced. If that is not possible, one of the anticholinergic anti-parkinsonian drugs may be given concurrently. - The M1 antagonists are drug of choice for drug induced parkinsonism. (Benzhexol).