Ketamine's Adverse Effects in Emergency Medicine

Ketamine's Role and Risks in Emergency Medicine

Ketamine is a critical drug in emergency medicine, used for its anesthetic and analgesic properties. However, it carries significant risks that emergency medicine clinicians must recognize and manage. This clinical review focuses on four primary adverse effects: acute psycho-perceptual adverse effects (PPAEs), ketamine-induced cystitis (KIC), ketamine-associated cholangiopathy, and ketamine use disorder (KUD).

Mechanisms and Clinical Context

Psycho-perceptual adverse effects occur in up to 92% of patients receiving sub-dissociative ketamine intravenously, though slow infusion can reduce this by approximately 40%. Ketamine-induced cystitis affects 25–27% of chronic users, presenting as a progressive uropathy that is partially reversible with early cessation. Ketamine-associated cholangiopathy, a sclerosing cholangitis-like syndrome, occurs in roughly 10% of chronic users. Ketamine use disorder encompasses dependence and withdrawal symptoms, necessitating careful management.

Policy and Research Implications

Emergency physicians are uniquely positioned to identify and manage these conditions, initiating treatment and connecting patients to specialized care. The rise in recreational ketamine use underscores the need for updated guidelines and training for emergency clinicians to address these adverse effects effectively. Policy makers should consider these findings when shaping regulations and educational programs for healthcare providers.

Risks, Unknowns, and Future Directions

While ketamine cessation is the most important intervention across all chronic toxicity syndromes, the long-term effects of ketamine use remain under-researched. Further studies are needed to understand the full spectrum of ketamine's adverse effects and to develop comprehensive management strategies. The global increase in recreational use highlights the urgency of these investigations.

Looking Forward: Managing Ketamine's Impact

As ketamine use continues to rise, both medically and recreationally, emergency medicine must adapt to manage its adverse effects effectively. Continued research and policy development will be crucial in ensuring that ketamine remains a safe and effective tool in emergency medicine, while minimizing its potential harms.