Safety and Preliminary Efficacy of MK0759 in Postherpetic Neuralgia (PHN)(0759-004)

Inclusion Criteria: * Age 18 to 85; diagnosis of postherpetic neuralgia with pain having persisted at least 6 months; dissatisfied with current regimen of pain control; able to complete study questionnaires, patient diary, and comply with daily study medication Exclusion Criteria: * Women of childbearing potential; history or evidence of a condition that, in the opinion of the investigator, may interfere with the study interpretation (e.g., diabetic neuropathy or fibromyalgia) or pose undue risk to undergo the course of medication required by the study (e.g., unstable heart disease, morbid obesity, kidney or liver disease).