Ketamine, a dissociative anaesthetic, has expanded its clinical use beyond anaesthesia to pain management and treatment-resistant depression. As an N-methyl-d-aspartate receptor antagonist, ketamine disrupts the excitatory neurotransmission via interaction with the opioid, alpha-amino-3-hydroxy-5-methyl-4-isooxazole-propionic acid receptor and serotonin pathways, contributing to its broad therapeutic potential. However, its use is not without risks. In patients with insulin resistance, ketamine's effect on glucose metabolism, mitochondrial function and oxidative stress are exacerbated. This paper explores ketamine's pharmacokinetics, cardiovascular impact and its cellular effects on cardiomyocytes, particularly in insulin-resistant individuals. The findings discussed emphasize the importance of careful administration and monitoring in these vulnerable populations to balance ketamine's therapeutic benefits against its potential risks in patients with underlying metabolic or cardiovascular conditions.