Zurnai (Purdue), an autoinjector formulation of the opioid antagonist nalmefene, has been approved by the FDA for intramuscular (IM) or subcutaneous (SC) emergency treatment of known or suspected opioid overdose in persons ≥12 years old. Naloxone, another opioid antagonist, has been available in single-use syringes for years. Both nalmefene and naloxone are also available in nasal sprays; some naloxone nasal sprays (Narcan, and others) are available over the counter.