Treatment of herpes zoster

Acyclovir, valaciclovir and famciclovir are efficacious in acute HZ and should be used in ophthalmic HZ and can ameliorate postherpetic neuralgia. Ideally antiviral therapy should be commenced within 72 hours of rash onset.[27] The choice of the drug will depend on the patient’s adherence, the doctor’s prescription habits and costs. However, all three drugs are equally effective and with a similar safety profile.[28],[29] Oral acyclovir has been the mainstay of HZ treatment, but it has poor bioavailability and needs to be given frequently. Valaciclovir and famciclovir need less frequent dosing (Table 3). There are no standard recommendations for treating children with HIV infection. However, the World Health Organization (WHO) guidelines suggest that the acyclovir dosage for HZ should be 80 mg/kg/day by mouth (maximum 800 mg per dose) or intravenous acyclovir 30 mg/kg/day in three doses for severe cases.[30] Novel drug therapies against herpes simplex and varicella-zoster viruses are currently in development and under clinical trials.[31]23

Table 3          Oral antiviral medications for herpes zoster



Duration of treatment

Most common side effect

Precaution and contraindication


800 mg  5 times a day

7-10 days or until lesions heal


gastrointestinal side effects

Dose adjust for renal impairment if creatinine clearance  < 25mL/min


1000 mg 3 times a day

7 days or until lesions heal


Dose adjust for renal insufficiency, if creatinine clearance < 50mL/min.

Thrombocytopenic purpura and haemolytic uraemic syndrome reported at 8000 mg doses in immunocompromised patients


500 mg 3 times a day

7 days or until lesions heal

Nausea, headache

Dose adjust for renal insufficiency if creatinine clearance  < 60mL/min

Source : Adapted from Dworkin, R, Johnson RW, Breuer J, Guann JW, Levin MJ, Backonja M, et al. Recommendations for the management of herpes zoster.   Clin Infect Dis 2007:44:S1