Multiple oral medications have demonstrated efficacy in relieving postherpetic neuralgia pain. Tricyclic antidepressants (TCAs), such as nortriptyline or desipramine, are effective in reducing postherpetic neuralgia pain but are limited by their numerous side effects. For every three people treated with a tricyclic antidepressant, one person is expected to have a clinically significant reduction in their pain (NNT=3). Additionally, of every sixteen people treated with a TCA, one person is expected to stop the medication due to a bothersome side effect, such as dry mouth, constipation, or urinary retention (number needed to harm=16). The anticonvulsant medications pregabalin and gabapentin also effectively relieve postherpetic neuralgia pain. Treatment with pregabalin leads to a reduction in pain intensity of 50% or more in one person out of every 4-5 people treated (NNT=4-5). Similarly, treatment with gabapentin also leads to a 50% reduction in pain intensity in one person out of every 7-8 people treated (NNT=7.5).