Situation: A 22-year-old man with a first episode of psychosis is admitted to an acute psychiatric unit. He receives haloperidol 5 mg intramuscularly (IM) for severe agitation and is then started on oral haloperidol. On day 12, two days after his oral haloperidol dose was increased, he paces the hallway, rocks from foot to foot while standing, and cannot stay seated through a meal. He says, "My legs won't let me sit still." His hallucinations have decreased. Which problem is MOST likely?

Akathisia is a subjective inner restlessness with an urge to move, often felt in the legs, appearing days to weeks after starting or increasing an antipsychotic. Timing after a dose increase and improving psychosis point to a drug effect rather than anxiety. It can raise suicide risk and is reported for dose reduction or other treatment.

Core mechanism
Haloperidol is a first-generation antipsychotic whose primary action is dopamine D2 receptor blockade. In the nigrostriatal pathway, this blockade produces the spectrum of extrapyramidal symptoms (EPS): acute dystonia, drug-induced parkinsonism, akathisia, and tardive dyskinesia ^[2]. The patient’s presentation—pacing, rocking foot-to-foot, inability to remain seated, and the statement “My legs won’t let me sit still”—is the classic motor picture of akathisia. Akathisia is defined by a subjective feeling of inner restlessness accompanied by an observable urge to move, most often experienced in the legs. ^[3][4]

Why this is akathisia, not anxiety or worsening psychosis
The timing is decisive. The patient’s oral haloperidol dose was increased two days before the restlessness appeared, and akathisia typically emerges days to weeks after initiation or dose escalation of an antipsychotic ^[4]. Equally important, his hallucinations have decreased. Worsening psychosis would not selectively improve positive symptoms while producing isolated motor restlessness; a drug-induced effect is far more consistent with this clinical trajectory. Anxiety from psychosis is a possible consideration, but the objective motor signs—pacing, shifting weight, inability to stay seated through a meal—are more specific for akathisia than for anxiety alone.

Differentiating the EPS subtypes

Feature	Akathisia	Parkinsonism	Tardive dyskinesia
Onset after dose change	Days to weeks	Days to weeks	Months to years
Core motor sign	Restlessness, pacing, inability to sit still	Bradykinesia, rigidity, tremor, shuffling gait	Involuntary choreoathetoid movements (face, tongue, limbs)
Subjective distress	Marked inner restlessness and urge to move	Usually less prominent subjective urge to move	Often less distressing or unnoticed by patient
Response to dose reduction	Often improves	Often improves	May persist or worsen

Key point! The patient’s dominant symptom is an urge to move with visible motor restlessness, not slowness, rigidity, or involuntary writhing movements. That pattern is akathisia, not parkinsonism or tardive dyskinesia.

Pathophysiology link to the basal ganglia
Akathisia has been linked to dopamine D2 receptor blockade in the basal ganglia . Functional imaging in a case of clinically manifest akathisia demonstrated bilateral putaminal hypermetabolism on [18F]FDG PET, supporting the view that akathisia is not simply a psychological reaction but a neurobiological consequence of altered basal ganglia activity . This helps explain why the symptom can be so distressing and why it may not respond to reassurance alone.

Clinical significance for nursing care
Akathisia is not a minor nuisance. It is associated with significant distress, can impair treatment adherence, and has been linked to increased suicide risk. ^[2][4] In a patient already vulnerable during a first psychotic episode, unrecognized akathisia may be misinterpreted as agitation or worsening illness, leading to an inappropriate antipsychotic dose increase. The correct nursing response is to recognize the motor pattern, report it promptly, and advocate for dose reduction or a medication change rather than additional antipsychotic dosing. Standard treatments such as benzodiazepines or anticholinergics may fail in severe cases, and adjunctive options such as low-dose mirtazapine have been reported to improve treatment-resistant akathisia ^[4]. Watch out! Increasing the haloperidol dose to treat what appears to be agitation would likely worsen akathisia, because the underlying mechanism is dopamine blockade rather than undertreated psychosis.