Adults: Initial and Recurrent Herpes Simplex Infections of the Skin and Mucous Membranes:
200 mg should be taken 5 times daily at approximately 4-hr interval omitting the nighttime dose. Treatment should continue for 5 days. In case of severe initial infection, treatment period may have to be extended.
In severely immunodepressed patient (eg, after marrow transplantation) or in patient with impaired absorption from the gut, the dose can be doubled to 400 mg or, alternatively, IV dosing could be considered.
The 1st dose should be administered as early as possible after the start of an infection and for recurrent episodes, this should preferably be during the prodromal period or when lesions first appear.
Suppression of Recurrent Genital Herpes Simplex Infections in Immunocompetent Adults:
A dose of acyclovir 200 mg should be taken 4 times daily at approximately 6-hr interval.
Many patients may be conveniently managed on a regimen of oral acyclovir 400 mg taken twice daily at approximately 12-hr interval. Dosage titration down to oral acyclovir 200 mg taken at approximately 8-hr intervals or even twice daily at approximately 12-hr intervals may prove effective. Some patients may experience breakthrough infections on total doses of acyclovir 800 mg.
Therapy should be interrupted periodically at intervals of 6-12 months, in order to observe possible changes in the natural history of the disease.
Prophylaxis of Herpes Simplex Infections in Immunocompromised Adults:
Acyclovir 200 mg should be taken 4 times daily at approximately 6-hr intervals. In severely immunocompromised patients (eg, after marrow transplant) or in patients with impaired absorption from the gut, the dose can be doubled to 400 mg, or alternatively IV dosing could be considered. The duration of prophylactic administration is determined by the duration of the period at risk.
Treatment of Varicella Zoster Infections in Adolescents (12-18 years):
A dose of oral acyclovir 800 mg should be taken 4 times daily for 5 days.
Treatment of Varicella Zoster and Herpes Zoster Infections in Adults:
A dose of oral acyclovir 800 mg should be taken 5 times daily at approximately 4-hr intervals, omitting the nighttime dose. Treatment should continue for 7 days.
In severely immunocompromised patients (eg, after marrow transplant) or in patients with impaired absorption from the gut, consideration should be given to IV dosing. Dosing should begin as early as possible after the start of an infection. Treatment yields better results if initiated as soon as possible after rash onset.
Dosage should be reduced in renal failure. The following is recommended. See table.
Click on icon to see table/diagram/image
Patients on haemodialysis should receive their usual appropriate daily dosage after each dialysis.
Use in the elderly:
In the elderly, total acyclovir body clearance declines, thus adequate hydration should be maintained. Special attention should be given to dosage reduction in elderly patients with impaired renal function.