Clinical progress note: Management of the hospitalized patient with medetomidine withdrawal.

Medetomidine is an ⍺2 adrenergic agonist that has rapidly emerged as an adulterant in the US illicit opioid supply. Clinicians should suspect medetomidine exposure when opioid overdoses respond poorly to naloxone. Medetomidine withdrawal is clinically distinct from opioid and xylazine withdrawal and should be suspected when a patient with opioid withdrawal presents with significant rebound sympathetic activation, including hypertension, tachycardia, tremor, agitation, and refractory vomiting despite opioid agonist treatment. Management requires concurrent treatment of opioid withdrawal, early use of ⍺2 agonists, and escalation to dexmedetomidine infusion for severe cases. Greater access to testing and prospective treatment data are needed.