SNRIs Versus SSRIs: Mechanisms of Action in Treating Depression and Painful Physical Symptoms

Patients with depression frequently experience painful somatic symptoms, which may be the only symptoms reported to the physician. In addition, patients with chronic painful medical illnesses frequently suffer comorbid depression. Antidepressants have been used successfully to treat psychological and physical symptoms of depression as well as chronic pain in nondepressed patients. Although the precise mechanisms by which antidepressants relieve symptoms of depression and pain are not clearly understood at this time, evidence suggests that serotonin and norepinephrine are involved in both. Antidepressants that act via modifying both serotonergic and noradrenergic neurotransmission may have an advantage compared with antidepressants that primarily affect only one of these neurotransmitter systems, particularly in patients with both depression and painful physical symptoms.