A nurse in a substance abuse clinic is assessing a client who is prescribed disulfiram (Antabuse). The client states he stopped the medication after developing severe nausea and vomiting. Which of the following does the nurse realize is most likely the cause of the client's symptoms?

Choice A Reason: An overdose of disulfiram can cause symptoms such as nausea and vomiting, but it is less likely to be the cause in this scenario. Overdoses typically present with more severe symptoms, including seizures and coma in rare cases¹. The client's symptoms are more consistent with a disulfiram-alcohol reaction. Choice B Reason: An allergic response to disulfiram can cause symptoms such as rash, itching, and swelling, but severe nausea and vomiting are not typical allergic reactions². Allergic reactions would also likely present with other symptoms such as difficulty breathing or hives, which are not mentioned in this case. Choice C Reason: While nausea and vomiting can be common side effects of disulfiram, the severity described by the client suggests a more significant reaction. Common side effects are usually milder and do not typically cause the client to stop the medication abruptly. Choice D Reason: The most likely cause of the client's severe nausea and vomiting is the consumption of alcohol while taking disulfiram. Disulfiram works by inhibiting the enzyme acetaldehyde dehydrogenase, leading to an accumulation of acetaldehyde when alcohol is consumed. This results in unpleasant effects such as severe nausea, vomiting, headache, and flushing. The client's symptoms align with this reaction, making it the most probable cause.