Profound Hyperthermia Associated With Fentanyl and Cocaine Use With Suspected Synephrine Adulteration.

Two patients presented to a tertiary care university hospital within 2 days of each other after recreational drug use with delayed and protracted hyperthermia. Synephrine was later found in high concentrations in biological samples as an unexpected drug adulterant. The first patient's presentation came with delayed recognition of hyperthermia and implementation of aggressive cooling measures; he entered multisystem organ failure with prolonged intensive care unit stay and significant morbidity. The second patient's hyperthermia was recognized promptly, and she received early, aggressive cooling, including deep sedation and ice water submersion. She left against medical advice from the hospital at her baseline 3 days after presentation. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Synephrine is a suspected adulterant that may be associated with profound hyperthermia. Early recognition of drug overdose and working knowledge of common adulterants can facilitate early targeted management, such as aggressive cooling measures, which may prevent morbidity and mortality.