If you sorted every PMHNP pharmacology item by topic, antipsychotic adverse effects and monitoring would be near the top. The reason is practical: these are the medications where a nurse practitioner's ongoing surveillance genuinely changes outcomes, and the exam is built to test surveillance.
The content divides cleanly into three blocks - movement effects, metabolic effects, and the emergencies - plus clozapine, which has its own rules and deserves its own study slot.
Movement effects, organised by time
The single most reliable way to answer an extrapyramidal item is to read the timeline in the stem first.
| Onset | Syndrome | Presentation | Typical direction of management |
|---|---|---|---|
| Hours to days | Acute dystonia | Sustained muscle contraction - torticollis, oculogyric crisis, laryngeal involvement | Urgent anticholinergic or antihistamine treatment; airway takes priority |
| Days to weeks | Akathisia | Subjective inner restlessness with an inability to stay still; often misread as agitation or anxiety | Reduce dose or switch; beta blockade or short-term benzodiazepine as adjunct |
| Weeks | Drug-induced parkinsonism | Bradykinesia, rigidity, tremor, masked facies | Reduce dose, switch to lower-risk agent, anticholinergic if needed |
| Months to years | Tardive dyskinesia | Involuntary choreoathetoid movements, classically orofacial | Reassess the need for the antipsychotic; VMAT2 inhibitors are the targeted option |
Two traps. Akathisia is routinely mistaken for worsening psychosis or anxiety, and the wrong answer - increase the dose - makes it worse; the exam likes this one. And anticholinergic agents help dystonia and parkinsonism but do not help tardive dyskinesia and may worsen it.
Screening for tardive dyskinesia
Structured movement assessment at regular intervals, using a standardised instrument such as the Abnormal Involuntary Movement Scale, is the expected practice for any patient on long-term antipsychotic treatment. Items asking "what should be done at this visit" often have this as the answer.
Metabolic effects and the monitoring schedule
Second-generation antipsychotics carry meaningful metabolic risk - weight gain, dyslipidaemia, insulin resistance and type 2 diabetes - and the risk is not uniform across agents. Clozapine and olanzapine sit at the high end. Several others, including aripiprazole, lurasidone and ziprasidone, sit lower.
The exam expects you to know that metabolic surveillance is scheduled, not opportunistic: baseline measurements before starting, frequent early reassessment in the first months when weight change is fastest, and then continuing periodic monitoring. The parameters are weight and body mass index, waist circumference, blood pressure, fasting glucose or glycated haemoglobin, and a fasting lipid panel, together with personal and family history.
Intervals are set by guidelines that get revised
Consensus monitoring intervals for weight, glucose and lipids have been revised over time and differ slightly between guideline bodies. Learn the principle - baseline, early reassessment, then ongoing periodic monitoring - and confirm the exact intervals in the current guideline your program or employer follows.
Other agent-specific effects worth knowing
- QTc prolongation - a particular consideration with ziprasidone and with intravenous haloperidol; relevant when other QT-prolonging drugs or electrolyte abnormalities are in the stem.
- Hyperprolactinaemia - most associated with risperidone, paliperidone and the first-generation agents; presents as galactorrhoea, amenorrhoea, gynaecomastia or sexual dysfunction.
- Orthostatic hypotension and sedation - prominent with quetiapine and clozapine, and a falls risk in older adults.
- Anticholinergic burden - relevant in older adults and in combination with other anticholinergic medications.
Neuroleptic malignant syndrome
NMS is rare, potentially fatal, and reliably examined. The classic picture is hyperthermia with severe generalised "lead-pipe" rigidity, altered mental status and autonomic instability, with a markedly elevated creatine kinase, developing over days rather than hours.
The management direction is immediate discontinuation of the offending agent and urgent medical management with aggressive supportive care; specific pharmacological agents may be used in severe cases. On an exam item, the correct first action is nearly always to stop the antipsychotic and escalate to emergency care - not to reduce the dose, not to add an anticholinergic.
Contrast it deliberately with serotonin syndrome, which develops over hours after a serotonergic change and features neuromuscular hyperexcitability - clonus and hyperreflexia - rather than lead-pipe rigidity.
Clozapine has its own chapter
Clozapine is reserved for treatment-resistant schizophrenia - conventionally after inadequate response to adequate trials of two other antipsychotics - and it has a specific role in reducing recurrent suicidal behaviour in schizophrenia and schizoaffective disorder. It is also the agent with the most demanding safety programme, and the exam tests that programme.
- Severe neutropenia. Absolute neutrophil count monitoring on a defined schedule is mandatory, with thresholds that determine whether treatment continues, is interrupted or is stopped.
- Myocarditis and cardiomyopathy. Highest risk in the early weeks; new chest pain, dyspnoea, tachycardia, fever or flu-like illness early in treatment is not a minor complaint.
- Seizures. Dose-related risk.
- Severe constipation and gastrointestinal hypomotility. Genuinely dangerous and under-recognised; bowel function is part of routine review.
- Sialorrhoea, sedation, orthostasis and metabolic effects. Common and frequently the reason patients want to stop.
- Interruptions matter. Missing doses for more than a short period requires re-titration rather than resuming the previous dose.
Confirm current monitoring thresholds and the requirements of the applicable risk management programme against current sources; these have been revised and are jurisdiction specific.
How to study this block
Build two tables from memory each week. The first is movement effects by time of onset with management direction. The second is the emergencies side by side - NMS, serotonin syndrome, anticholinergic toxicity - with onset speed, muscle findings, reflexes, pupils and skin. Those two tables answer a disproportionate share of the antipsychotic items you will meet.
Key points
- Read the timeline first: hours means dystonia, days to weeks means akathisia, weeks means parkinsonism, months to years means tardive dyskinesia.
- Akathisia is commonly mistaken for worsening psychosis; increasing the dose is the classic wrong answer.
- Metabolic monitoring is scheduled - baseline, early reassessment, then ongoing - covering weight, blood pressure, glucose and lipids.
- NMS develops over days with lead-pipe rigidity and high CK; serotonin syndrome develops over hours with clonus and hyperreflexia.
- Clozapine carries its own mandatory monitoring programme: neutrophil counts, early myocarditis risk, seizures and severe constipation.