Case Reports in Medicine the screen is designed for, and a drug’s pharmacokinetics [12]. To be detected in a urine drug screen, the substance must be absorbed, metabolized, and then renally excreted. In general, most standard urine screens for opioids detect codeine, morphine, and metabolites of the two. Fentanyl is a fully synthetic opiate that is structurally dissimilar from morphine and codeine; therefore, the metabolites of fentanyl are also dissimilar [12]. Fentanyl is primarily hepatically metabolized, and the inactive metabolites (primarily nor- fentanyl) are excreted in the urine. Only 10% of the parent drug is excreted unchanged in the urine [11]. In order to detect a fentanyl-related opioid intoxication, a urine drug screen would need to assay exclusively for fentanyl or the predominant metabolite norfentanyl. The treatment approach in this patient was twofold: limit opioid toxicity and facilitate passage of the ingested patches. Naloxone, a pure opioid antagonist at all opioid receptor sites, has long been utilized in the ED and intensive care unit for the treatment of opioid intoxication [11]. Whole bowel irrigation using polyethylene glycol or a similar osmotic laxative has been used successfully in the treatment of other intoxications, such as lithium or ingestion of extended release products [13, 14]. While activated charcoal is often a ﬁrst choice for oral intoxications, we chose to utilize a diﬀerent approach for two reasons. First, the eﬃcacy of single-dose- activated charcoal decreases over time. In a 2005 position paper, Chyka and Seger demonstrated decreased eﬃcacy as the time from poisoning is increased from 30 minutes postingestion to 180 minutes [15]. These authors questioned the utility of charcoal use after one hour postingestion. Secondly, drug must be available in the gastrointestinal tract and must be bound by charcoal for this treatment modality to be eﬀective [16]. Since the time from ingestion to presentation to our ED was over 2 hours, the drug was, at least partially, housed within the transdermal system, and there are no data on adsorption of fentanyl to activated charcoal, we opted away from this therapeutic option. Our approach was to utilize a continuous infusion of naloxone until the patient passed the patches in his stool and returned to his baseline mental status. Unfortunately, the patches were never recovered in the patient’s stool and were later presumed to have passed prior to transfer to the intensive care unit, although it is possible that the patient extracted the fentanyl from the patches and disposed them in a conventional means prior to law enforcement and EMS arrival. Fentanyl absorbed across the buccal membrane has an elimination half-life of up to 12 hours; therefore, treating and monitoring the patient for 72 hours would ensure, using the most conservative estimate, 6 half-lives had passed and at least 98.5% of the drug had been eliminated [10]. Lastly, the patient coingested 6–8 milligrams of alpra- zolam, perhaps leading to benzodiazepine overdose. While a speciﬁc antidote for benzodiazepine ingestion exists (i.e., Flumazenil), we did not utilize it because of the unknown duration of alprazolam (or other benzodiazepine) use. Flumazenil may precipitate benzodiazepine withdrawal or seizures, and routine administration of Flumazenil has been questioned, leading some to recommend that the drug rarely be utilized in benzodiazepine overdose [17, 18]. 3 Additionally, despite an 11-hour half-life, the duration of action of alprazolam is 5.1 ± 1.7 hours [11]. We, therefore, adopted a more conservative approach when treating this benzodiazepine ingestion by providing supportive care and whole bowel irrigation. 4. Conclusions Our case adds to the small body of literature which describes oral ingestion of a fentanyl patch and is the only to describe a treatment modality for this situation. Contact time with the oral mucosa may be the most important factor in deter- mining severity of oral fentanyl ingestion, as bioavailability is signiﬁcantly higher via the buccal membrane. Financial Disclosure No ﬁnancial support is provided. References [1] DURAGESIC (fentanyl transdermal system) [package insert], Ortho-McNeil-Janssen Pharmaceuticals, Raritan, NJ, USA, July 2009. [2] “How to Abuse Fentanyl Patches,” Drugs-Forum, December 2010, http://www.drugs-forum.com/forum/showthread.php?t =13456. [3] “Sandoz Fentanyl Patch versus Mylan Fentanyl Patch,” Blue- light, December 2010, http://www.bluelight.ru/vb/showthread .php?t=310561. [4] B. A. Goldberger, M. I. Fileger, M. L. Merves, and M. S. Gold, “Fentanyl use and abuse: new emerging trends in drug abuse [abstract],” College on Problems of Drug Dependence, 2005. [5] R. van Rijswijk and C. van Guldener, “A delirious patient with opioid intoxication after chewing a fentanyl patch ,” Journal of the American Geriatrics Society, vol. 54, no. 8, pp. 1298–1299, 2006. [6] S. Thomas, R. Winecker, and J. P. Pestaner, “Unusual fentanyl patch administration,” American Journal of Forensic Medicine and Pathology, vol. 29, no. 2, pp. 162–163, 2008. [7] K. L. Woodall, T. L. Martin, and B. A. McLellan, “Oral abuse of fentanyl patches (Duragesic ): seven case reports,” Journal of Forensic Sciences, vol. 53, no. 1, pp. 222–225, 2008. [8] H. J. Carson, L. D. Knight, M. H. Dudley, and U. Garg, “A fatal- ity involving an unusual route of fentanyl delivery: chewing and aspirating the transdermal patch,” Legal Medicine, vol. 12, no. 3, pp. 157–159, 2010. 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