A client is prescribed haloperidol (Haldol). The nurse notices the client is restless, constantly moving, and unable to sit still. What adverse effect is this?

EXTRAPYRAMIDAL SYMPTOMS (EPS) OF ANTIPSYCHOTICS: AKATHISIA: Subjective restlessness; constant movement; inability to sit still; patient may rock, shift weight, pace; often described as 'I just can't stay still, I need to keep moving'; can be severely distressing and lead to medication refusal; TREATMENT: Dose reduction; propranolol or benztropine; DYSTONIA (acute): Sudden involuntary muscle contractions; tortured postures; can affect neck (torticollis), jaw (trismus), eyes (oculogyric crisis); treated with benztropine (anticholinergic); PSEUDOPARKINSONISM: Mask-like face, pill-rolling tremor, shuffling gait, rigidity — similar to Parkinson's disease; TARDIVE DYSKINESIA (TD): LATE onset after months/years of antipsychotic use; repetitive involuntary movements (lip smacking, tongue protrusion, choreoathetoid limb movements); may be irreversible; NEUROLEPTIC MALIGNANT SYNDROME (NMS): Life-threatening; HIGH FEVER, rigidity, altered consciousness, autonomic instability — medical emergency, stop medication.