Malignant neurolept hyperthermia (NMS) seen in all except –
**Core Concept**
Malignant neuroleptic syndrome (NMS) is a life-threatening neurological disorder associated with the use of antipsychotic medications, particularly phenothiazines and butyrophenones. It is characterized by muscle rigidity, fever, autonomic dysfunction, and altered mental status.
**Why the Correct Answer is Right**
NMS is thought to result from an excessive release of dopamine and acetylcholine, leading to an increase in muscle tone and metabolism. The pathophysiology involves the blockade of dopamine receptors, particularly D2 receptors, which leads to an upregulation of dopamine receptors and an increase in dopamine release. This excessive dopamine release then triggers the symptoms of NMS.
**Why Each Wrong Option is Incorrect**
* **Option A:** is incorrect because NMS has been associated with the use of haloperidol, a typical antipsychotic medication that blocks dopamine receptors.
* **Option B:** is incorrect because NMS has been linked to the use of risperidone, an atypical antipsychotic that also blocks dopamine receptors.
* **Option C:** is incorrect because NMS has been reported in association with the use of olanzapine, another atypical antipsychotic that blocks dopamine receptors.
**Clinical Pearl / High-Yield Fact**
It's essential to recognize that NMS can occur with various antipsychotic medications, and patients with a history of NMS should avoid future use of these medications.
**Correct Answer: A. Clozapine**