BIIE-0246 is a drug used in scientific research which acts as a potent and selective antagonist for the Neuropeptide Y receptor Y<sub>2</sub>. It was one of the first non-peptide Y<sub>2</sub>-selective antagonists developed, and remains among the most widely used tools for studying this receptor. It has been used to demonstrate a role for the Y<sub>2</sub> subtype as a presynaptic autoreceptor limiting further neuropeptide Y release, as well as modulating dopamine and acetylcholine release. It has also been shown to produce several behavioural effects in animals, including reducing alcohol consumption in addicted rats and anxiolytic effects, although while selective Y<sub>2</sub> agonists are expected to be useful as anorectics, BIIE-0246 did not appear to increase appetite when administered alone.