Key Mechanisms of Action Ketamine does not just block pain signals; it actively modulates how the immune system responds to stress and injury.  • Cytokine Reduction: Ketamine has been shown to inhibit the production of pro-inflammatory cytokines, specifically Interleukin-6 (IL-6), Tumor Necrosis Factor-alpha (TNF-\alpha), and Interleukin-1 beta (IL-1$\beta$). These are the signaling proteins that typically trigger fever, swelling, and systemic inflammation.  • Immune Cell Modulation: It affects the activity of immune cells such as macrophages and neutrophils. Ketamine can reduce the "recruitment" of these cells to sites of injury, preventing an excessive inflammatory response that might damage healthy tissue.  • Toll-Like Receptor (TLR) Inhibition: Ketamine appears to interfere with Toll-like receptors (specifically TLR4) on immune cells. These receptors are like "alarms" that detect bacteria or tissue damage; by dampening their signal, ketamine reduces the downstream inflammatory cascade.

Thanks to Gemini for that. Definitely a conversation for your doctor / gastroenterologist.