Duloxetine: a review of its pharmacology and use in chronic pain management.

Duloxetine is a serotonin and norepinephrine reuptake inhibitor that possesses antidepressant and pain-relieving properties. Compared with other antidepressants, it has a high affinity for both norepinephrine and serotonin reuptake transporters, which are relatively balanced. Analgesic onset has been observed within the first week of administration in randomized controlled trials and is likely obtained by enhancing the tone of the descending pain inhibition pathways of the central nervous system. Randomized trials have documented significant analgesic effects for managing chronic pain associated with fibromyalgia and diabetic peripheral neuropathic pain. Studies have also suggested that pain associated with major depressive disorder can be reduced with this medication. Modest effects for headache, osteoarthritic pain, and pain secondary to Parkinson disease have also been documented, but data are obtained from single-blinded or open-label trials that require further corroboration with larger randomized studies. Duloxetine has not yet been directly compared with other antidepressants or anticonvulsants for the treatment of pain syndromes.