Mianserin-d3 is a deuterated compound of Mianserin. Mianserin has a CAS number of 24219-97-4. Mianserin, an H1 receptor reverse agonist, is a psychoactive compound in the tetracyclic antidepressant (TeCA) treatment family. Mianserin has antidepressant, antianxiety, antiemetic, hypotrophic, hypnotic and antihistamine effects, and can be used as a combination of norepinephrine and specific serotonin to treat depression.