Extrapyramidal symptoms (EPS), also known as extrapyramidal side effects (EPSE), are drug-induced movement disorders that include
acute and tardive symptoms. These symptoms include
dystonia (continuous spasms and muscle contractions),
akathisia (motor restlessness),
parkinsonism (characteristic symptoms such as rigidity,
bradykinesia, and
tremor), and
tardive dyskinesia (irregular, jerky movements). Antipsychotics are often discontinued due to inefficacy or intolerable side effects such as extrapyramidal symptoms.