WBR0445

Author	[[PageAuthor::Rim Halaby, M.D. [1]]]
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Pharmacology
Sub Category	SubCategory::Neurology
Prompt	[[Prompt::A 28 year old male patient who is previously healthy is brought to the emergency department for excessive somnolence, impaired balance, and impaired motor function. The physician suspects a benzodiazepine overdose. Flumazenil is quickly administered at the appropriate dose and infusion rate. A few seconds after administration of flumazenil, the patient’s wife arrives to the emergency department and tells the physician that her husband attempted suicide and in fact ingested excessively two drugs: A benzodiazepine and a tricyclic antidepressant. Which of the following symptoms will the patient most likely experience following administration of flumazenil in this case of co-ingestion of benzodiazepine and tricyclic antidepressant?]]
Answer A	AnswerA::Seizure
Answer A Explanation	AnswerAExp::Seizure is a potential adverse event in the case of flumazenil antidote of when co-ingestion of BZD and TCA.
Answer B	AnswerB::Chest pain
Answer B Explanation	AnswerBExp::Chest pain is not an adverse effect of flumazenil use in this case.
Answer C	AnswerC::Excessive sedation
Answer C Explanation	AnswerCExp::Flumazenil is expected to reverse the excessive sedation that is caused by BZD.
Answer D	AnswerD::Renal failure
Answer D Explanation	AnswerDExp::Renal failure is not an adverse effect of flumazenil use in this case.
Answer E	AnswerE::Acalculous cholecystitis
Answer E Explanation	AnswerEExp::Acalculous cholecystitis is not an adverse effect of flumazenil use in this case.
Right Answer	RightAnswer::A
Explanation	[[Explanation::Flumazenil should be used carefully in patients who have a previous history of seizures, such as a past medical history of epilepsy, or when there is suspicion of mixed overdose. In the case when benzodiazepine (BZD) is co-ingested with tricyclic antidepressants (TCA), the use of flumazenil as an antidote to benzodiazepine to reverse the sedative effects of benzodiazepines can actually expose or unmask the side effect of tricyclic antidepressants, such as seizures, that can occur within only a few minutes of administration of flumazenil. The seizure is not believed to be a side effect of flumazenil itself, but rather an unmasking of the side effect of the tricyclic antidepressant that is apparent only when the effect of benzodiazepine is reversed by flumazenil. As a result, seizure risk must always be assessed in patients who require flumazenil use and a risk-to-benefit ratio in those patients must always be considered as to whether flumazenil is to be administered or not. Educational Objective: In the case when benzodiazepine (BZD) is co-ingested with tricyclic antidepressants (TCA), the use of flumazenil as an antidote to benzodiazepine to reverse the sedative effects of benzodiazepines can actually unmask the side effect of tricyclic antidepressants, such as seizures, that can occur within a few minutes of administration of flumazenil. References: Spivey WH. Flumazenil and seizures: analysis of 43 cases. Clin Ther. 1992; 14(2):292-305. Haverkos GP, DiSalvo RP, Imhoff TE. Fatal seizures after flumazenil administration in a patient with mixed overdose. Ann Pharmacother. 1994;28(12):1347-9. Educational Objective: References: ]]
Approved	Approved::No
Keyword	WBRKeyword::benzodiazepine, WBRKeyword::tricyclic, WBRKeyword::antidepressant, WBRKeyword::flumazenil, WBRKeyword::seizure, WBRKeyword::adverse, WBRKeyword::drug, WBRKeyword::reaction, WBRKeyword::side, WBRKeyword::effect, WBRKeyword::coingestion, WBRKeyword::mixed, WBRKeyword::overdose
Linked Question	Linked::
Order in Linked Questions	LinkedOrder::