Antidepressants and chronic pain

Successful treatment of pain syndromes is one of the most common and most difficult problems facing family physicians. Frequently analgesics provide inadequate treatment, and clinicians are forced to consider alternatives. This article reviews the neurophysiologic similarities between depression and the chronic pain syndromes and describes several well-designed double-blinded studies that give evidence for the efficacy of antidepressants in chronic pain syndromes. These studies conclude that antidepressants should be considered in chronic pain syndromes that do not respond to analgesics. For chronic pain, antidepressants should be started at a low dosage and increased in a stepwise manner until an improvement in the pain occurs or intolerable side effects intervene. Side effects are a bothersome aspect of antidepressant therapy but are more tolerable at the doses generally needed for pain relief than at antidepressive doses. At least three weeks of antidepressant therapy is generally needed to gain significant relief of symptoms.