Which medication may be given to treat muscle rigidity in NMS?

• A. Bromocriptine
• B. Dantrolene
• C. Benztropine
• D. Haloperidol

Answer: (B)

When managing muscle rigidity in Neuroleptic Malignant Syndrome, the primary goal is to rapidly relax the stiff, rigid muscles and cool the body. Dantrolene does this directly by acting on skeletal muscle to decrease calcium release from the sarcoplasmic reticulum, which lowers muscle contraction and heat production. This makes it the most effective first-line agent for reducing the characteristic rigidity in NMS.

Bromocriptine can be used as an adjunct after stabilization to help restore dopamine signaling, but it is not the immediate agent that relieves the acute rigidity. Benztropine targets extrapyramidal symptoms in other contexts but does not address the severe rigidity seen in NMS. Haloperidol, being a dopamine antagonist, can worsen NMS and should be avoided.