🩺 Clinical Quiz
Case:
- 22-year-old woman with severe depression
- On Haloperidol, Sertraline, and Lorazepam
- Overdosed on multiple medications ~24 hours ago
- Now delirious, hallucinating, febrile (105°F), tachycardic
- Limb tremor and increased muscle tone present
What is the most likely diagnosis?
A) Neuroleptic Malignant Syndrome (NMS)
B) Serotonin Syndrome
C) Acute Dystonia
D) Benzodiazepine Withdrawal
E) Tardive Dyskinesia
📖 Explanation
Correct Answer: A) Neuroleptic Malignant Syndrome (NMS)
This patient most likely has Neuroleptic Malignant Syndrome (NMS) due to recent overdose of haloperidol, a dopamine-blocking antipsychotic.
Features supporting NMS:
- 🔥 Very high fever (105°F / 40.5°C)
- 🧠 Delirium and hallucinations
- 💪 Increased muscle tone (rigidity)
- 🤝 Tremor
- ❤️ Tachycardia (115/min)
- 💊 History of haloperidol overdose
The classic presentation of NMS is: Hyperthermia + Muscle Rigidity + Altered Mental Status + Autonomic Instability.
Why not the other options?
- B) Serotonin Syndrome: Usually causes hyperreflexia, clonus, and diarrhea; rigidity is less prominent.
- C) Acute Dystonia: Causes focal muscle spasms but not high fever or delirium.
- D) Benzodiazepine Withdrawal: Requires abrupt cessation rather than overdose.
- E) Tardive Dyskinesia: Chronic involuntary movements without fever or rigidity.
📝 Content Summary
A 22-year-old woman with severe depression treated with haloperidol, sertraline, and lorazepam ingested multiple tablets of her medications approximately 24 hours before presentation.
She subsequently developed vomiting, headache, unsteady gait, delirium, hallucinations, high-grade fever (105°F), tachycardia, limb tremor, and increased muscle tone. Neurological examination showed flexor plantar responses.
The most likely diagnosis is Neuroleptic Malignant Syndrome (NMS), a life-threatening adverse reaction associated with dopamine-blocking agents such as haloperidol. The combination of hyperthermia, altered mental status, rigidity, and autonomic instability strongly supports NMS.
Serotonin syndrome is less likely because characteristic findings such as clonus and hyperreflexia are absent. Benzodiazepine withdrawal is also unlikely, as the history involves overdose rather than abrupt discontinuation.
📊 Neuroleptic Malignant Syndrome (NMS) vs Serotonin Syndrome
| Feature | Neuroleptic Malignant Syndrome (NMS) | Serotonin Syndrome |
|---|---|---|
| Cause | Dopamine blockade (e.g., Haloperidol) | Excess serotonin (e.g., SSRIs, MAOIs) |
| Onset | Gradual (1–3 days) | Rapid (within hours) |
| Temperature | Very high fever common | High fever may occur |
| Mental Status | Delirium, confusion, stupor | Agitation, confusion |
| Muscle Findings | Severe "lead-pipe" rigidity | Hypertonia with clonus |
| Reflexes | Normal or decreased | Hyperreflexia |
| Clonus | Absent | Present (key feature) |
| Tremor | May occur | Common |
| Autonomic Signs | Tachycardia, BP instability, diaphoresis | Tachycardia, hypertension, diaphoresis |
| Creatine Kinase (CK) | Markedly elevated | Mildly elevated or normal |
| Key Diagnostic Clue | Rigidity + antipsychotic exposure | Clonus + hyperreflexia + serotonergic drug |
| Treatment | Stop antipsychotic, supportive care, dantrolene/bromocriptine | Stop serotonergic drugs, supportive care, cyproheptadine |
🔑 Keyword
- Neuroleptic malignant syndrome overdose
- Haloperidol-induced NMS
- NMS clinical case study
- Neuroleptic malignant syndrome diagnosis
- NMS vs serotonin syndrome
- Psychiatry board review NMS
- Antipsychotic drug toxicity case
- Neuroleptic malignant syndrome symptoms
🫀 Cardiology 🫁 Respiratory 🧠 Neurology 🩸 Hematology 🧪 Nephrology 🦠 Gastroenterology 🏥 Hepatology 🦴 Rheumatology 💉 Endocrinology 🩺 ABG 🧩 Psychiatry ☠️ Poisoning 🌿 Environment
🏠 Back to Home | 📬 Contact Us | 📋 About Us