PZ-II-029 is primarily used in research settings as a selective antagonist for the orexin OX2 receptor. It is employed to study sleep-wake regulation, particularly in models related to insomnia and narcolepsy. Due to its ability to cross the blood-brain barrier, it is valuable in central nervous system studies investigating the role of orexin signaling in arousal and sleep disorders. It has also been utilized in preclinical studies to evaluate potential therapeutic pathways for treating addiction and drug-seeking behavior, as orexin pathways are involved in reward processing. Its selectivity makes it a useful tool for distinguishing OX2 receptor-mediated effects from those involving the OX1 receptor.