What characterizes akathisia?

Akathisia is characterized by an unbearable inner restlessness and the compelling need to be in constant motion, making it difficult for an individual to sit still. Patients with akathisia often fidget, pace, or exhibit other forms of restlessness, which can be distressing and significantly impact their quality of life. This condition is frequently associated with certain medications, particularly antipsychotics, and it manifests as a side effect rather than an inherent neurological issue.

In this context, the other options describe different movement disorders or states. Severe muscle rigidity refers to a condition often seen in extrapyramidal symptoms, involuntary facial movements can indicate tardive dyskinesia, and extreme lethargy suggests a state of profound fatigue which is not typical of akathisia. Understanding the specific nature of akathisia is crucial, as it influences treatment decisions and patient management strategies.