Naltrexone in the Treatment of Ketamine Use Disorders: A Case Report and Literature Review.
Rishi Verma, Tom Colley, Claire Waldock, Louisa Bird, Irene Guerrini
Journal of Addiction Medicine October 2, 2025 DOI: 10.1097/adm.0000000000001589 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Case report Double-blind Peer reviewed |
|---|---|
| Sample size | 1 |
| Population | 25-year-old woman diagnosed with ketamine use disorder enrolled in an outpatient specialist addiction service |
| Intervention | Naltrexone |
| Dose | 25 mg/day initially, increased to 50 mg/day after 7 days |
| Topics | Ketamine Esketamine |
| Keywords | Ketamine dependence Ketamine desire Naltrexone Substance-related disorders |
| Citations | 1 |
| Key findings | Naltrexone at 50 mg/day was associated with reduced ketamine cravings and sustained abstinence in a patient with ketamine use disorder. |
Abstract
Nonprescribed use of ketamine has increased worldwide due to its hallucinogenic and psychedelic effects. Ketamine use disorders (KUDs) are marked by intense cravings and tolerance, which often trigger relapses and worsen recovery outcomes, defined as sustained ketamine abstinence with reduced cravings, resolved withdrawal symptoms, and improved psychosocial functioning. Currently, there are no approved pharmacological treatments for KUDs. This report examines the off-label use of naltrexone in a patient with KUDs. The case was a 25-year-old woman diagnosed with KUDs enrolled in an outpatient, specialist addiction service. The patient presented with ketamine daily use and intense cravings when trying to stop. The patient was prescribed oral naltrexone at the initial dose of 25 mg/day, which was increased to 50 mg/day after 7 days. After the initiation of treatment, the patient experienced a marked reduction in ketamine cravings. She was able to maintain abstinence and to progress in her recovery. The positive response to naltrexone suggests its potential as an effective intervention for managing KUDs. Our findings are consistent with 2 prior reports that have highlighted the use of naltrexone in KUDs. The 2 previous case reports indicated that naltrexone at the dosage of 50 mg/day successfully helped the patients to achieve abstinence. Studies have shown that naltrexone reduces the antidepressant effects of ketamine in treatment-resistant depression, indicating an overlap between the opioid system and ketamine's NMDA receptor activity. Larger, double-blind studies are needed to evaluate naltrexone's efficacy, safety, and optimal dosing for KUDs.
Comparable studies
Other case reports and case series on ketamine, most cited first.
Citations in the library
Cites 5
- Psychedelics Promote Structural and Functional Neural Plasticity Cell Reports June 1, 2018
- Ketamine use: a review Addiction July 21, 2011
- Attenuation of Antidepressant Effects of Ketamine by Opioid Receptor Antagonism American Journal of Psychiatry August 29, 2018
- The Pharmacological Management of Ketamine Use Disorder: A Systematic Review. Journal of Addiction Medicine
- A survey of drug liking and cravings in patients using sublingual or intranasal ketamine for treatment resistant depression: A preliminary evaluation of real world addictive potential Frontiers in Psychiatry November 17, 2022