What is a possible adverse reaction to prochlorperazine (Compazine)?

What is a possible adverse reaction to prochlorperazine (Compazine)?

• A. Possible dystonic reactions
• B. Sedation
• C. Hypertension
• D. Nausea

Answer: (A)

Dopamine receptor blockade in the nigrostriatal pathway can produce extrapyramidal symptoms, and acute dystonic reactions are a well-known adverse effect of prochlorperazine. This medication blocks D2 receptors not only in the chemoreceptor trigger zone to control nausea, but also in motor pathways, which can cause involuntary muscle contractions, facial grimacing, torticollis, or oculogyric crises. These reactions often appear within hours to a few days of starting treatment, especially in younger patients, and are treatable with an anticholinergic such as benztropine or diphenhydramine. Sedation can occur and hypertension is not typical (hypotension is more common with this drug), and while nausea is the condition being treated, it doesn’t reflect an adverse reaction in the same way dystonia does.

Dopamine receptor blockade in the nigrostriatal pathway can produce extrapyramidal symptoms, and acute dystonic reactions are a well-known adverse effect of prochlorperazine. This medication blocks D2 receptors not only in the chemoreceptor trigger zone to control nausea, but also in motor pathways, which can cause involuntary muscle contractions, facial grimacing, torticollis, or oculogyric crises. These reactions often appear within hours to a few days of starting treatment, especially in younger patients, and are treatable with an anticholinergic such as benztropine or diphenhydramine.

Sedation can occur and hypertension is not typical (hypotension is more common with this drug), and while nausea is the condition being treated, it doesn’t reflect an adverse reaction in the same way dystonia does.