Akathisia

Akathisia is a movement disorder characterized by a subjective sense of inner restlessness accompanied by observable motor symptoms. Individuals often feel unable to sit still and may pace, rock, shift their weight, tap their feet, or fidget constantly. Anxiety, irritability, and sleep disturbance commonly accompany the restlessness and can be distressing.

Most cases arise as a side effect of dopamine-blocking medications, particularly antipsychotics used to treat schizophrenia and bipolar disorder. It can also occur with other dopaminergic or antiemetic drugs, such as metoclopramide or prochlorperazine, and less commonly with certain antidepressants or drugs that affect dopamine function. Acute akathisia typically begins within days of a dose increase; tardive akathisia can appear after long-term exposure or persist after stopping the offending drug.

Pathophysiology is not fully understood but is believed to involve reduced dopaminergic activity in the nigrostriatal pathway and imbalanced signaling in basal ganglia and related circuits. Serotonergic and noradrenergic systems may modulate the symptoms, contributing to the complex presentation of inner restlessness and movement.

Diagnosis is clinical, based on history and examination, and often aided by standardized scales such as the Barnes Akathisia Rating Scale (BARS). Differential diagnosis includes other drug-induced movement disorders, anxiety disorders, and restless leg syndrome. Exclusion of other neurological or psychiatric causes is important.

Management centers on addressing the underlying medication. This may involve dose reduction, switching to a different antipsychotic with a lower risk, or careful cross-titration. Symptomatic treatments include propranolol and short-acting benzodiazepines. Anticholinergic drugs are less effective for akathisia and may worsen tardive symptoms. In some cases, agents such as VMAT2 inhibitors or partial dopamine agonists may be considered under specialist care. Regular monitoring and patient education are important.