Compliance Problems with Naltrexone (Vivitrol)

"Despite the ease of outpatient dosing and its ability to effectively block the euphoric effects of ?-opioid agonists, naltrexone has had limited success for relapse prevention when compared with maintenance t­herapy with methadone or buprenorphine. Studies have shown that fewer patients choose to start t­reatment with naltrexone,²¹ and few of those remain compliant with medications.^22,23 Patients who have been treated previously with methadone are also less likely to sustain opioid abstinence with naltrexone compared with individuals who had only had naltrexone for treatment of opioid dependence.^24–26 Poor compliance with naltrexone is also associated with higher dosages of heroin used daily.²⁶ Of patients in treatment with naltrexone, many drop out quickly within the first few weeks, especially if they used opioids again after missing ­ naltrexone doses.²⁷ The numbers of drop-outs from naltrexone treatment are very high, with over one quarter dropping out after a few days,²⁸ and almost one-half dropping out in first few weeks.²⁹"