A 31-year-old man is hospitalized after sustaining multiple injuries during a motor vehicle collision. The patient is not conscious initially, and no information is available regarding his medical history. Two days after initial hospitalization, he experiences palpitations and difficulty sleeping. Shortly thereafter, the patient suffers a generalized tonic-clonic seizure. When he recovers, he tells the physician that he usually takes medications for anxiety, bipolar disorder, and chronic low back pain. Temperature is 36.7 C (98.1 F), blood pressure is 129/82 mm Hg, pulse is 92/min, and respirations are 14/min. He appears anxious, tremulous, and diaphoretic. Withdrawal from which of the following medications is the most likely explanation for this patient's presentation?

Question

A 31-year-old man is hospitalized after sustaining multiple injuries during a motor vehicle collision.  The patient is not conscious initially, and no information is available regarding his medical history.  Two days after initial hospitalization, he experiences palpitations and difficulty sleeping.  Shortly thereafter, the patient suffers a generalized tonic-clonic seizure.  When he recovers, he tells the physician that he usually takes medications for anxiety, bipolar disorder, and chronic low back pain.  Temperature is 36.7 C (98.1 F), blood pressure is 129/82 mm Hg, pulse is 92/min, and respirations are 14/min.  He appears anxious, tremulous, and diaphoretic.  Withdrawal from which of the following medications is the most likely explanation for this patient's presentation?

Quizplus · Accepted Answer

This patient's presentation is consistent with benzodiazepine withdrawal (eg, lorazepam), which is most often characterized by rebound anxiety, tremor, insomnia, and sympathetic hyperactivity (eg, diaphoresis, palpitations). In severe cases, psychotic symptoms (eg, hallucinations, delusions), seizures, and even death may occur. Risk of withdrawal is greatest with short-acting agents (eg, alprazolam), prolonged use, and use of higher doses. Benzodiazepines act on the GABA_A receptor, enhancing the action of the natural ligand, GABA. The body adapts to chronic benzodiazepine exposure by downregulating the GABA_A receptor, leading to tolerance, a phenomenon in which the same dose of a medication yields decreasing effects over time. This same adaptive downregulation process is responsible for the withdrawal syndrome when benzodiazepines are discontinued and the body is unable to balance opposing excitatory neurotransmitters. Benzodiazepine withdrawal is treated by starting a patient on a long-acting benzodiazepine (eg, diazepam) and planning for an extended, gradual taper. (Choices A and G) The anticonvulsants lamotrigine and valproate are used in bipolar disorder for their mood-stabilizing properties. Withdrawal from these medications would not produce seizures in a patient without an underlying seizure disorder. (Choices B and E) Withdrawal from lithium or quetiapine, when used to treat bipolar disorder, may be associated with a risk for manic relapse and nonspecific rebound psychiatric symptoms (eg, anxiety, restlessness). However, withdrawal from these medications would not explain this patient's symptoms or seizure. (Choice D) Opioid (eg, oxycodone) withdrawal is characterized by nausea, vomiting, diarrhea, lacrimation, dilated pupils, and piloerection. (Choice F) Selective serotonin reuptake inhibitor (eg, sertraline) withdrawal presents with rebound anxiety/dysphoria, dizziness, headache, and nausea. Educational objective: Benzodiazepine withdrawal is characterized by anxiety, tremor, insomnia, and sympathetic hyperactivity (eg, diaphoresis, palpitations). Severe benzodiazepine withdrawal may also be accompanied by psychosis, seizures, or death. __________ References: Benzodiazepine harm: how can it be reduced? (http://www.ncbi.nlm.nih.gov/pubmed/22882333) Sedative-hypnotic drug withdrawal syndrome: recognition and treatment. (http://www.ncbi.nlm.nih.gov/pubmed/28186869)

A 31-Year-Old Man Is Hospitalized After Sustaining Multiple Injuries During