Reboxetine mesylate is primarily used as an antidepressant, specifically in the treatment of major depressive disorder. It functions as a selective norepinephrine reuptake inhibitor (NRI), which helps increase the levels of norepinephrine in the brain, thereby improving mood and reducing symptoms of depression. It is particularly beneficial for patients who do not respond well to other types of antidepressants, such as SSRIs. Additionally, it has been explored for its potential in managing attention deficit hyperactivity disorder (ADHD) and certain anxiety disorders, although its use in these areas is less common. The mesylate salt form enhances its solubility and stability, making it more effective for pharmaceutical formulations.