A Study of Vacyless® Versus Valtrex® in Patients With Herpes Zoster

Inclusion Criteria: * Men and women between 20 to 80 years of age. * Patients with a clinical diagnosis of HZ as evidenced by a unilateral dermatomal rash. * Patients with zoster-related rash (rash severity is greater than or equal to mild). * Patients are able to be enrolled into the study 72 hours from appearance of rash (for example, lesions or vesicles). * Patients provided written informed consent. * Patients who are able to complete all study visits per protocol. * Men and premenopausal women must agree to practice a barrier method of birth control or the use of a spermicide for one month after the last dose of study drug (oral contraceptives are not permitted). Subject should be withdrew from the study if contraceptions are faild. Exclusion Criteria: * Women who are pregnant or lactating. * Patients with multidermatomal or disseminated HZ (greater than 20 lesions beyond the dermatomes adjacent to the primarily involved dermatome). * Patients with HZ ophthalmicus, defined as cutaneous lesions in the dermatome associated with the ophthalmic division of the trigeminal nerve * Patients with history of impaired renal function, (e.g., calculated creatinine clearance less than 50 mL/min/1.73 m2) * Patients are taking narcotic analgesic routinely for a chronic pain condition * Patients are taking tricyclic antidepressants * Patients who received systemic antivirals with activity against VZV within the past 30 days, or a topical antiviral to treat their current HZ * Patients with immunosuppressive or immunodeficient condition resulting from: disease (e.g., HIV) corticosteroid use (except intermittent or topical/inhaled beclomethasone dipropionate or equivalent \< 800 mcg/day), or other immunosuppressive/cytotoxic therapy (cancer chemotherapy or organ transplantation ) * Patients with any other condition (e.g., extensive psoriasis, chronic pain syndrome, cognitive impairment) that, in the opinion of the site investigator, might interfere with the evaluations required by the study * Patients who are not ambulatory (bed-ridden or homebound); hospitalized patients may be enrolled if they are ambulatory and able to complete the study requirements * Patients with history of allergy to valacyclovir hydrochloride and acetaminophen * Patients are unlikely to adhere to protocol follow-up