Author: Katie Sprinkle, MD Educational Pearl:   Carbon monoxide (CO) is the leading cause of death from poison world-wide CO forms from the combustion of any carbon based product Patients often present with non specific symptom like headache, vomiting, and malaise Consider this diagnosis with multiple people presenting with similar symptoms from a single location Treatment is with high flow oxygen (i.e. non-rebreather) Hyperbaric therapy is controversial and up for debate - discussion with local consultants may help guide this management/transfer Tobacco smokers typically have elevated levels of carbon monoxide at baseline   Editor’s Note: smoking hookah for one hour may be the equivalent of smoking nearly 100 cigarettes References: Jacob P, Abu Raddaha AH, Dempsey D, et al. Nicotine, carbon monoxide, and carcinogen exposure after a single use of a water pipe. Cancer Epidemiol Biomarkers Prev. 2011;20(11):2345-53. Ng PC, Long B, Koyfman A. Clinical chameleons: an emergency medicine focused review of carbon monoxide poisoning. Intern Emerg Med. 2018 Mar;13(2):223-229. doi: 10.1007/s11739-018-1798-x. Epub 2018 Feb 12. Review. Erratum in: Intern Emerg Med. 2018 Mar 22;:. PubMed PMID: 29435715. American College of Emergency Physicians Clinical Policies Subcommittee (Writing Committee) on Carbon Monoxide Poisoning:., Wolf SJ, Maloney GE, Shih RD, Shy BD, Brown MD. Clinical Policy: Critical Issues in the Evaluation and Management of Adult Patients Presenting to the Emergency Department With Acute Carbon Monoxide Poisoning. Ann Emerg Med. 2017 Jan;69(1):98-107.e6. doi: 10.1016/j.annemergmed.2016.11.003. PubMed PMID: 27993310. Guzman JA. Carbon monoxide poisoning. Crit Care Clin. 2012 Oct;28(4):537-48. doi: 10.1016/j.ccc.2012.07.007. Review. PubMed PMID: 22998990. Summarized by Travis Barlock, MS4 | Edited by Erik Verzemnieks, MD