Treatment of post-herpetic neuralgia: antidepressants.

Five controlled clinical trials and extensive clinical experience have shown that amitriptyline and several other antidepressants reduce the severity of post-herpetic neuralgia. Studies in post-herpetic neuralgia and in painful diabetic neuropathy suggest that blockade of norepinephrine reuptake is the most important action accounting for pain relief; selective agents such as desipramine may be useful in patients unable to tolerate amitriptyline side effects. The selective serotonin reuptake inhibitors, zimelidine and paroxetine, have shown little effectiveness in neuropathic pain, but small studies in diabetic neuropathy have shown that paroxetine and citalopram have modest effects. Studies of the latter agents in post-herpetic neuralgia, concentration-response studies of amitriptyline, and studies of drug combinations including antidepressants may lead to improved treatment.