SR18662 is primarily used in research settings as a potent and selective antagonist for the orexin receptor system, specifically targeting the OX1 receptor. Its main application lies in neuroscience and pharmacology studies focused on sleep-wake regulation, addiction, and reward-related behaviors. Due to its ability to modulate orexin signaling, SR18662 is employed to investigate the role of orexin in anxiety, stress responses, and drug-seeking behavior. It is also utilized in preclinical models to explore potential treatments for substance use disorders, particularly those involving alcohol and psychostimulants. Its selectivity makes it a valuable tool for dissecting the functional differences between OX1 and OX2 receptor pathways in behavioral assays.