Naltrexone XR May Be Associated With Dysphoria, Suicide Ideation

injection, syringe, vaccine
injection, syringe, vaccine
Monthly injections of naltrexone extended-release may induce a dysphoric state and suicidal ideation in some patients.

The following article is part of conference coverage from the 2019 American Psychiatric Association Annual Meeting (APA 2019) in San Francisco, CA. Psychiatry Advisor’s staff will be reporting breaking news associated with research conducted by leading experts in psychiatry. Check back for the latest news from APA 2019.

SAN FRANCISCO — Monthly injections of naltrexone extended-release (naltrexone XR) may induce a dysphoric state and suicidal ideation in some patients, according to a case study presented at the American Psychiatric Association Annual Meeting, held May 18-22, 2019, in San Francisco, California. These adverse effects underscore the need for clinicians to give patients an oral test dose of naltrexone XR before initiating treatment.

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Researchers described the case of a woman aged 36 with opioid dependence who presented with severe anxiety, suicidal ideation, and dysphoria following an initial naltrexone injection. The patient had a diagnosis of congenital Horner syndrome, and had developed sick sinus syndrome following the implantation of a pacemaker. She had been treated at several rehabilitation centers for opioid dependence prior to this episode, and reported no history of suicide attempts or psychiatric hospitalization. The patient’s buprenorphine/naloxone regimen had been tapered over the previous month in preparation for her treatment with naltrexone XR. She tested negative for opioids at the time of naltrexone XR injection, as indicated by urine analysis, and denied having been administered an oral naltrexone test dose.

As she reported to the psychiatry team which examined her 2 days after the treatment, the patient experienced severe anxiety, panic, and agitation within 3 hours of receiving the naltrexone XR injection, symptoms that escalated to depression and suicidal ideation the next day, with the planning to overdose on heroin. She reported these episodes as being distinct from prior withdrawal symptoms. Injectable naltrexone XR is known to have 2 peaks of serum concentration, the first at 2 hours, and the second at 2 to 3 days, which coincide with the patient’s initial dysphoria and suicidal ideation, respectively.

“In this era of the opioid epidemic, the use of naltrexone XR will only increase given its success in assisting with abstinence from opioids. Clinicians should be aware of the need to administer an oral test dose, as well as educate and be vigilant of the existence and time course of potential adverse reactions, including dysphoria and even suicidal ideation,” concluded the authors of the case study.

For more coverage of APA 2019, click here.


O’Brien LL, Viguera AC, Sola C. Naltrexone-induced dysphoria. Poster presented at: American Psychiatric Association Annual Meeting; May 18-22, 2019; San Francisco, CA. Abstract 17.