What type of medication is Esketamine classified as?

Esketamine is classified as an antidepressant because it is a variant of ketamine, primarily utilized in the treatment of major depressive disorder, particularly in cases where patients have treatment-resistant depression. Esketamine acts on the glutamatergic system and is thought to rapidly alleviate depressive symptoms, which is distinct from traditional antidepressants that typically target serotonin or norepinephrine levels. It is administered as a nasal spray in clinical settings, reflecting its unique mechanism of action and the emergent nature of its use in psychiatric treatment compared to other antidepressants. This classification is significant for understanding its application in mental health treatment and the specific patient populations it is designed to help.