extrapyramidal symptom

Extrapyramidal symptoms (EPS) are a group of movement disorders that can arise from the long-term use of certain medications, particularly antipsychotics that affect dopamine signaling in the brain. These symptoms are often delayed in onset, hence the term "tardive".1

The most common form of EPS is tardive dyskinesia, characterized by repetitive, involuntary movements, especially in the face, mouth, and jaw, such as lip smacking or chewing motions. While the exact cause is not fully understood, it's believed to result from chronic blockage of dopamine receptors in the brain.1

EPS can also be associated with Parkinsonism, a group of neurological disorders causing progressive loss of motor function due to the degeneration of dopamine-producing neurons in the substantia nigra. This loss disrupts dopamine signaling, leading to symptoms like tremors, rigidity, and difficulty initiating movement. Medications like levodopa are used to manage Parkinsonism symptoms by increasing dopamine levels or mimicking its effects.23