WZ811 is primarily used in scientific research as a selective antagonist for the kappa opioid receptor (KOR). Its main application lies in neuroscience and pharmacology studies, where it helps investigate the role of KOR in pain modulation, mood regulation, and addictive behaviors. Due to its high selectivity and ability to cross the blood-brain barrier, WZ811 is valuable in in vivo experiments to block KOR activity and study downstream physiological effects. It has been used to explore potential treatments for depression, anxiety, and substance use disorders by modulating the endogenous opioid system. WZ811 is not used clinically and remains restricted to preclinical research.