Impact of Intravenous Naltrexone on Intravenous Morphine-Induced High, Drug Liking, and Euphoric Effects in Experienced, Nondependent

Abstract Background: Opioid analgesics can be abused by crushing followed by solu-bilization and intravenous injection to attain rapid absorption. Morphine sulfate and naltrexone hydrochloride extended release capsules (EMBEDA, MS-sNT), indicated for management of chronic, moderate to severe pain, contain pellets of morphine sulfate with a sequestered naltrexone core. Should product tampering by crushing occur, the sequestered naltrexone is intended for release to reduce morphine-induced subjective effects. Objective: This study compared self-reports of high, euphoria, and drug-liking effects of intravenous morphine alone versus intravenous morphine combined with naltrexone in a clinical simulation of intravenous abuse of crushed MS-sNT. Methods: This single-center, randomized, double-blind, crossover study char-acterized subjective effects of naltrexone administered intravenously at the same ratio to morphine present in MS-sNT. Subjects were male and had used prescription opioids five or more times within the previous 12 months to ge