Health risks associated with non-medical use of ketamine in France: National surveillance insights from the French Addictovigilance Network, 2019-2023.

Background: While ketamine is widely used in anesthesia and pain management, its non-medical use is increasing worldwide. In France, surveillance data indicate a sharp rise in ketamine-related disorders, but comprehensive characterization of affected patients and associated complications remains limited.

Aims: To examine trends on ketamine in France from 2019 to 2023, and describe severe associated complications, with a focus on urinary, biliary, and ketamine use-related disorders, using data from the French Addictovigilance Network.

Methods: Two authors reviewed all ketamine-related cases reported to the French Addictovigilance Network between 2019 and 2023 and recorded in the French National Pharmacovigilance Database. In this retrospective descriptive analysis of national surveillance data, we included cases involving clinical complications related to ketamine use or abuse. Data were extracted on patient sociodemographic, use patterns, co-substance, and clinical features related to ketamine use (complications, seriousness, medical care).

Results: We included 411 cases with 497 clinical manifestations, representing a 16-fold increase over 5 years. The median age was 23 years, and 59.1% of cases were classified as serious, with emergency or intensive care admissions frequently required. The main complications included ketamine use disorders (137 cases), psychiatric symptoms (124 cases), and neurological disorders (93 cases). Urinary tract toxicity was reported in 36 cases, with several requiring cystectomy and bladder reconstruction, and 8 cases involved cholangitis or cholestasis. Daily or regular use, often via the intranasal route, and polydrug use were common.

Conclusions: These findings demonstrate a marked increase in ketamine-related complications in France, particularly among young users. Severe urinary and biliary complications, alongside rising reports of ketamine use disorder, highlight an urgent need for awareness among clinicians, systematic screening, and targeted harm reduction and clinical screening strategies.