Extrapyramidal side effects (EPS) refer to a collection of movement disorders that can arise as a result of the use of certain medications, particularly antipsychotic medications. EPS typically manifest as involuntary or abnormal movements in various regions of the body, including the limbs, face, neck, tongue, or trunk. These side effects occur due to the interference with the normal functioning of the extrapyramidal system, which is a part of the central nervous system responsible for coordinating and modulating voluntary movements.
The extrapyramidal system consists of several components, such as the basal ganglia and certain pathways within the brain. Medications that block dopamine receptors in these pathways, like typical antipsychotics, can disrupt the delicate balance of neurotransmitters involved in motor control, leading to the onset of EPS. Some common extrapyramidal side effects include dystonia (sustained muscle contractions causing repetitive or twisting movements), parkinsonism (akinetic rigid syndrome with symptoms like tremors, muscle stiffness, and impaired balance), akathisia (restlessness and a compulsive need to move), and tardive dyskinesia (repetitive, involuntary, and purposeless movements typically affecting the face and limbs).
Although newer atypical antipsychotic medications have been developed to minimize extrapyramidal side effects, they are not entirely free from them. The severity and duration of EPS can vary depending on factors such as the specific medication, dosage, and individual susceptibility. Prompt recognition, careful monitoring, and appropriate management of extrapyramidal side effects are crucial for ensuring optimal patient care and minimizing any potential impact on quality of life.
