Narcan Narcan Narcan® Narcan Narcan® Narcan opioid antagonist naloxone hydrochloride Narcan narcan Narcan Narcan Narcan Narcan Narcan Narcan® Narcan Narcan Narcan Narcan® - (Naloxone Hydrochloride Injection, USP) NARCAN. Narcan Narcan FDA has noted potential side effects