Post-herpetic neuralgia

This chapter discusses the role of Tricyclic antidepressants, Anticonvulsants, Opioids, Local anesthetics, Capsaicin, and Ketamine in post-herpetic neuralgia (PHN). PHN is one of the more commonly encountered manifestations of neuropathic pain. Post-herpetic neuralgia is one of the many neuropathies for which tricyclic antidepressants (TCAs) are useful. A placebo-controlled trial testing the anticonvulsant gabapentin found that one patient in three achieved significant pain relief. Multicenter trial of pregabalin found this agent to be useful for PHN, with a response rate of approximately one in three patients. Local anesthetics such as lidocaine may be efficacious when used for peripheral nerve blockade. Meta-analysis has been conducted to assess and compare some of the many treatments for PHN. Available data from RCT data for PHN show that roughly half of patients respond to TCAs or oxycodone, one in three improves with gabapentin, and approximately one in five achieves significant relief with capsaicin.