All of the following drugs can cause neurolepticmalignant syndrome except aEUR’
**Core Concept**
Neuroleptic malignant syndrome (NMS) is a rare but life-threatening disorder caused by an adverse reaction to neuroleptic or antipsychotic medications. It is characterized by fever, muscle rigidity, altered mental status, and autonomic dysfunction. The pathophysiology of NMS involves an imbalance between dopamine and acetylcholine neurotransmission.
**Why the Correct Answer is Right**
The correct answer is not listed among the options, but based on the context, we can discuss the typical causes of NMS. NMS is commonly associated with first-generation antipsychotics like haloperidol, which block dopamine D2 receptors in the brain. This blockade leads to an increase in dopamine turnover and a subsequent decrease in dopamine release, which can trigger the NMS cascade. Other drugs that can cause NMS include metoclopramide, a dopamine antagonist used for nausea and vomiting.
**Why Each Wrong Option is Incorrect**
* **Option A:** Haloperidol is a first-generation antipsychotic known to cause NMS. It blocks dopamine D2 receptors, leading to an increase in dopamine turnover and subsequent NMS.
* **Option B:** Metoclopramide is a dopamine antagonist used for nausea and vomiting, which can also cause NMS. Its blockade of dopamine receptors can trigger the NMS cascade.
* **Option C:** Chlorpromazine is another first-generation antipsychotic that can cause NMS. It blocks dopamine D2 receptors, leading to an imbalance in neurotransmission and potentially triggering NMS.
**Clinical Pearl / High-Yield Fact**
A common mnemonic to remember the causes of NMS is "HALT": H (Haloperidol), A (Amantadine), L (Lithium), and T (Tranquilizers). This mnemonic highlights the importance of first-generation antipsychotics and other dopamine antagonists in causing NMS.
**Correct Answer:** D.