Before receiving naltrexone for the first time, individuals must either undergo a period of medically supervised withdrawal or otherwise already be abstinent from opioids for a period of time. Clinicians may be hesitant to newly initiate naltrexone in individuals given these requirements.

Clinicians may not have sufficient familiarity with naltrexone or belief in its effectiveness, especially compared to more common medications for opioid use disorder, such as buprenorphine and methadone, or they may believe that treatment for opioid use disorder is generally outside their scope of practice.