Inclusion Criteria:

• Male and female adults at least 18 years of age
• Patients with signs and symptoms consistent with acute herpes zoster disease, namely, a dermatomal vesicular rash which may be preceded by pain and parasthesias in the days before vesicular eruption
• Herpes Zoster associated rash present for ≤ 72 hours
• Patients who are deemed to be immunocompetent based on history and physical exam

Exclusion Criteria:

• Females who are pregnant or nursing
• History or clinical manifestations of significant metabolic, hematological, pulmonary, ischemic, or unstable heart disease, gastrointestinal, neurological, psychiatric, renal, urological, endocrine, opthalmologic, or immune mediated disease including HIV or HBsAg positivity
• Chronic genital herpes
• Patients who received cytotoxic or immunosuppressive drug therapy within 3 months prior to study participation
• Previous vaccinations against Herpes Zoster
• Patients with > 50% of vesicles crusted at screen
• Patients who received topical or systemic antiviral medications or immunomodulatory agents for herpes zoster viral infections or capsaicin within 4 weeks of study participation
• Patients with a history of congenital, acquired, or corticosteroid induced immunodeficiency, including malignancy, significantly impaired renal function (creatinine clearance < 50 cc/min), and impaired hepatic function (ALT or AST levels > 3 times the upper limit of normal)
• QTc > 500msec
• Patients with a history of intolerance or hypersensitivity to acyclovir, penciclovir, valacyclovir, or famciclovir
• Patients with gastrointestinal dysfunction that might interfere with drug absorption
• Patients, considered by the investigator, for any reason, to be an unsuitable candidate for receiving the study drug