Used as an active pharmaceutical ingredient in antidepressant medications, primarily for the treatment of major depressive disorder. It functions as a serotonin-norepinephrine reuptake inhibitor (SNRI), helping to restore the balance of certain natural substances in the brain, which improves mood, sleep, appetite, and energy levels. It is also prescribed for anxiety disorders and chronic pain conditions such as diabetic neuropathy and fibromyalgia. The hydrochloride salt form enhances solubility and bioavailability, making it suitable for oral dosage forms like tablets or capsules.