Valproic acid is used for a variety of clinical indications including seizures, migraine prophylaxis and treatment, and bipolar disorder. A metabolite of valproic acid, thought to be propionic acid, has the ability to increase ammonia levels by inhibiting a step in the hepatic urea cycle, which may lead to valproic acid-induced hyperammonemic encephalopathy. As a result, patients treated with valproic acid presenting with signs and symptoms of acute mental status changes, increased seizure frequency, and/or gastrointestinal symptoms should be evaluated for elevated ammonia concentrations.

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Carbon monoxide (CO) poisoning may be the most common cause of fatal poisonings worldwide. ¹ The majority of poisonings occur in the Fall and Winter. It is that time of year when heaters that have lain dormant all summer are flicked on, sometimes in enclosed areas, introducing CO fumes into homes. The pathophysiology is complex, and not fully understood, but all ED physicians should be aware of the signs and symptoms of CO toxicity, and know how to treat it.

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Prochlorperazine is a commonly used medication in EM. In certain patients prochlorperazine does wonders for migraines, and remains a great antiemetic choice for undifferentiated nausea/vomiting when ondansetron is ineffective. However, prochlorperazine has antidopinamergic activity increasing the chances of extrapyramidal symptoms (EPS), such as akathisia, dystonia, parkinsonism, and rarely tardive dyskinesia. A common practice in the ED is to give diphenhydramine with prochlorperazine to attenuate EPS.  Does this really work? What is the evidence?

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Misuse of prescription opioids is one of the defining health problems of our generation.  The dramatic rise of opioid analgesic prescriptions in the US and Canada has been well documented, and opioids represent the most common cause of fatal prescription overdoses. On every shift, in every emergency department in the country, physicians struggle with the concerns of patients presenting with common pain complaints. Seeking to manage their patients’ symptoms in the face of dramatically rising prescription opioid misuse and fatal overdose, emergency physicians are  challenged to distinguish those who are simply seeking pain relief, those who are seeking opioid prescriptions due to addiction, and those who fit both categories. Emergency care providers are also charged with balancing the pressures of meeting clinical care and patient satisfaction goals while fulfilling our moral obligation to provide primary and secondary prevention of opioid misuse.

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