2 drowsiness. On arrival, law enforcement corroborated the ex- wife’s description of the patient ingesting the two fentanyl patches and gave an account of the event to the ED physician and pharmacists. The patient admitted to regular use of methamphetamine, opioids, and benzodiazepines and had a past medical history bipolar disorder for which he took no medications. His review of systems was negative, except for the dizziness, drowsiness, and altered mental status, and admission physical examination was unremarkable. The patient’s initial set of vitals after 2 milligrams of intravenous naloxone were as follows: afebrile, blood pressure 106/77, heart rate 63, respiratory rate 16, and oxygen saturation 100% on 2 liters via nasal cannula. Initial chemistry, liver function tests, and complete blood count were all within normal limits. A urine drug screen was negative for opioids, but positive for amphetamines and benzodiazepines. Serum ethanol, acetaminophen, and salicylate levels were all negative. A serum fentanyl level was not obtained. The patient arrived in the ED at 0900. Upon arrival, the patient was stabilized and assessed. At 1000, a naloxone drip (8 micrograms per milliliter in 0.9% sodium chloride) was initiated at 0.4 milligrams per hour and slowly titrated up to 2 milligrams per hour due to returning signs of opioid toxicity (bradycardia, respiratory rate <12, and declining neurologic exam). Additionally, whole bowel irrigation with polyethylene glycol 3350 via nasogastric tube was initiated secondary to concerns for ingested patches creating a depot- like eﬀect. The patient had one bowel movement in the ED (no documentation that patches or remnants were passed) and remained hemodynamically and neurologically stable until transfer to the medical intensive care unit at approximately 2200 that evening. His naloxone drip was titrated down to 0.2 milligrams per hour around 1200 of his second hospital day and was eventually discontinued that evening at 2300. He did not receive any additional naloxone after this point. In total, he received approximately 15 milligrams of naloxone over these two days. He remained cardiovascularly and neurologically stable throughout his stay in the medical ICU, was subsequently downgraded to the medical ﬂoor on hospital day 3 (48 hours after admission), and discharged from the hospital on day 4 at 1100. 3. Discussion Multiple ingestions of fentanyl patches have been reported, with outcomes ranging from transient symptoms of overdose (e.g., hypotension, altered mental status) to death. Van Rijswijk and Van Guldener described the case of an 81-year- old male with a history of multiple myeloma, osteoporosis, and delirium who was found chewing on a fentanyl patch [5]. His nurse promptly removed the patch from the patient’s mouth; however, thirty minutes later, the patient became less arousable and hypotensive. After administration of naloxone 0.4 milligrams and intravenous saline, the patient’s mental status and blood pressure returned to baseline. Thomas and colleagues published a case report of a 42-year-old male with known drug abuse, including hospitalization for drug overdose, who died subsequent to oral ingestion of Case Reports in Medicine fentanyl patches [6]. Upon autopsy, the decedent had three pieces of fentanyl patches in his stomach. Further history reveals that the decedent commonly chewed, sucked on, and swallowed fentanyl patches to obtain a high. Lastly, Woodall and colleagues reported a case series of seven deceased patients in whom oral administration of a fentanyl patch was suspected to have contributed to their death [7]. Decedents ranged in age from 20 to 51 years and had oral and transbuccal administration of a patch based on witness reports or evidence of patch residue in the oral cavity. Postmortem fentanyl serum concentrations ranged from 7 to 97 ng/mL, whereas typical serum concentrations from single dose studies with fentanyl transbuccal tablets (100– 800 mcg) yield peak serum concentrations between 0.25 and 1.59 ng/mL [9]. More recently, Carson and colleagues presented a case of a 28-year-old white male who died in the ED after chewing and aspirating a transdermal fentanyl patch. On autopsy, the decedent had a beige foreign body (later identiﬁed as the transdermal device) lodged in the mainstem bronchus, and postmortem toxicological analysis revealed a serum fentanyl level of 8.6 ng/mL [8]. Fentanyl serum levels are not performed in our facility’s laboratory, and determining them would require sending them to an outside laboratory. Due to the typical return time on these types of labs, we felt an admission fentanyl level would be of little beneﬁt to the medical team three days later. Fentanyl is 50–65% bioavailable across the buccal mem- brane when administered as a transbuccal system (e.g., lozenge and troche) [1, 9, 10]. However, when ingested orally, fentanyl undergoes extensive ﬁrst-pass metabolism, resulting in 20% escaping hepatic metabolism and entering the systemic circulation. Therefore, as alluded to in published case reports, the time fentanyl stays in contact with the oral mucosa directly translates to the systemic absorption and the severity of the overdose. Case reports describe either chewing or sucking on the fentanyl patch, leading to extensive contact time between the oral mucosa and the inner gel matrix. Additionally, the reservoir of a fentanyl patch houses a large dose of fentanyl. In the case of our patient, a 50 microgram per hour patch stores 8400 micrograms of fentanyl [1]. If the entire reservoir contents of one fentanyl patch were ingested, approximately 1680 micrograms would enter the systemic circulation. Assuming a 25% reduction for cross-tolerance, this fentanyl dose is equivalent to 126 milligrams of intra- venous morphine [11]. However, ingesting an intact patch would not necessarily result in signiﬁcant gastrointestinal absorption (i.e., the drug would still remain within the intact system). If the entire contents of one patch were removed and administered transbuccally, this systemic level would be approximately three times that achieved with gastrointestinal absorption (i.e., approximately 5000 micrograms of fentanyl or 375 milligrams of intravenous morphine). Thus, chewing or sucking on a fentanyl patch increases contact time with the buccal membrane and liberates drug from the transdermal system, greatly increasing systemic absorption. Our patient’s ED urine drug screen for opioids was negative; however, this does not necessarily exclude an opioid ingestion. A urine drug screen’s ability to detect substances is based on the assay, the drug (and metabolites, if applicable)