Dosage in Adults: Treatment of herpes simplex infections: 200 mg (1 tsp) should be taken 5 times daily at approximately 4 hour intervals omitting the night time dose for 5 days. But in severe initial infections, this may have to be extended.
In severely immunocompromised patients (e.g. after marrow transplant) or in patients with impaired absorption from the gut, the dose can be doubled to 400 mg (2 tsp) ACICLOVIR or alternatively intravenous dosing could be considered.
Dosing should begin as early as possible after the start of an infection, for recurrent episodes this should preferably be during the prodromal period or when lesions first appear.
Suppression of herpes simplex infections in immunocompetent patients: 200 mg (1 tsp) should be taken 4 times daily at approximately 6 hour intervals.
Many patients may be conveniently managed on a regimen of 400 mg (2 tsp) twice daily at approximately 12 hour intervals.
Dosage titration down to 200 mg (1 tsp) taken thrice daily at approximately 8 hour intervals or even twice daily at approximately 12 hour intervals, may prove effective.
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 patients: 200 mg (1 tsp) should be taken 4 times daily at approximately 6 hour intervals.
In severely immunocompromised patients (e.g. after marrow transplant) or in patients with impaired absorption from the gut, the dose can be doubled to 400 mg (2 tsp) or alternatively, intravenous dosing could be considered.
The duration of prophylactic administration is determined by the duration of the period at risk.
Treatment of herpes zoster infections: 800 mg (4 tsp) Aciclovir should be taken 5 times daily at approximately 4 hour intervals omitting the night time dose. Treatment should continue for 7 days.
In severely immunocompromised patients or in patients with impaired absorption from the gut, consideration should be given to intravenous 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 in Children: Treatment of herpes simplex infections, and prophylaxis of herpes simplex infections in the immunocompromised: >2 yrs: should be given adult dosages.
<2 yrs: should be given half the adult dose of Aciclovir.
No specific data are available on the suppression of herpes simplex infections in immunocompetent children.
Treatment of chicken pox in children up to 2 yrs: Aciclovir is administered 20 mg/kg on the basis of body weight 4 times daily for 5 days. Dosing should begin as early as possible after the start of a chicken pox rash, treatment yields better results if initiated within 24 hours after rash onset.
Patients with renal impairment: Treatment of herpes simplex infections: In the management of herpes simplex infections in patients with impaired renal functions, the recommended oral doses will not lead to accumulation of Aciclovir above levels that have been established by intravenous infusion.
For patients with severe renal impairment (creatinine clearance less than 10 mL/minute) an adjustment of dosage to 200 mg (1 tsp) Aciclovir twice daily at approximately 12 hour intervals is recommended.
Treatment of herpes zoster infections: For patients with severe renal impairment (creatinine clearance less than 10 mL/minute) an adjustment of dosage to 800 mg (4 tsp) Aciclovir 3-4 times daily at approximately 6 to 8 hour intervals is recommended.
Dosage in Elderly: In the elderly, total Aciclovir body clearance declined in parallel with creatinine clearance. Adequate hydration of elderly patients taking high oral doses of Aciclovir should be maintained.
Special attention should be given to dosage reduction in elderly patients with impaired renal function. Or as prescribed by a physician.
