A 30-year-old man with neuroleptic malignant syndrome is being managed in the ICU with cooling, IV fluids, and discontinuation of haloperidol. Rigidity and temperature remain severe after 24 hours. Which drug acts by blocking calcium release from the skeletal muscle sarcoplasmic reticulum and is used in this setting?
- A Dantrolene ✓
- B Bromocriptine
- C Propranolol
- D Amantadine
Correct answer: A. Dantrolene
Explanation
Dantrolene binds the ryanodine receptor and blocks release of calcium from the sarcoplasmic reticulum, directly reducing skeletal muscle contracture and heat generation. Bromocriptine is also used in NMS but works centrally as a dopamine agonist. Propranolol and amantadine are not standard treatments for established NMS with persistent severe rigidity.
Reference: Kaplan and Sadock's Synopsis of Psychiatry, 12th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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