Pharmacokinetics and brain distribution of ketamine after nasal administration.
Journal of pharmaceutical and biomedical analysis October 15, 2025 Zihe Yang, Linjie Li, Bin Deng et al. 3 citations
After intranasal administration in rats, ketamine rapidly enters the bloodstream, reaching a peak concentration of 8002 ng/mL within about 5 minutes, then declines to near zero by about 3 hours, with a half-life of 27 minutes. Tissue analysis shows the highest ketamine levels in the kidneys, followed by the liver. Within the brain, ketamine concentrates most in the hypothalamus and hippocampus, with lower amounts in the striatum and prefrontal cortex. These findings clarify how ketamine distributes throughout the body and brain after intranasal delivery, providing a basis for understanding its clinical use in treating depression.