Serotonin–norepinephrine reuptake inhibitor

Serotonin–norepinephrine reuptake inhibitors (SNRIs), also known as serotonin–noradrenaline reuptake inhibitors, are a class of antidepressant drugs used in the treatment of major depressive disorder (MDD) and other mood disorders. They are sometimes also used to treat anxiety disorders, obsessive-compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), chronic neuropathic pain, and fibromyalgia syndrome (FMS), and for the relief of menopausal symptoms.

SNRIs are potent inhibitors of the reuptake of serotonin and norepinephrine. These neurotransmitters are known to play an important role in mood. SNRIs can be contrasted with the more widely used selective serotonin reuptake inhibitors (SSRIs), which act upon serotonin alone.

The human serotonin transporter (SERT) and norepinephrine transporter (NET) are membrane proteins that are responsible for the reuptake of serotonin and norepinephrine. Balanced dual inhibition of monoamine reuptake can possibly offer advantages over other antidepressant drugs by treating a wider range of symptoms. SNRIs, along with selective serotonin reuptake inhibitors (SSRIs) and norepinephrine reuptake inhibitors (NRIs), are second-generation antidepressants. Over the past two decades, second-generation antidepressants have gradually replaced first-generation antidepressants, such as tricyclic antidepressants (TCAs) and monoamine oxidase inhibitors (MAOIs) as the drugs of choice for the treatment of MDD. This is mainly because of their improved tolerability and safety profile.