Acyclovir 5% Topical
Acyclovir 5% Topical is used for: Herpes virus infections of skin
As 5% oint/cream: Apply to the affected skin 5-6 times/day for 5-10 days.
Renal impairment. Pregnancy, lactation. Neurological abnormalities with significant hypoxia, serious hepatic or electrolyte abnormalities. Maintain adequate hydration. Lactation: Excretion in milk unknown; systemic exposure is minimal after topical application.
Pregnancy category: B Lactation: Excretion in milk unknown; systemic exposure is minimal after topical application
Probenecid, cimetidine and mycophenolate mofetil may increase the plasma concentration of aciclovir. Increased nephrotoxic effects w/ drugs that affect renal physiology (e.g. ciclosporin, tacrolimus).
Side effects of Acyclovir 5% Topical : >10% Burning/stinging (30%) 1-10% Pruritus (4%) <1% Dry lips (<1%), Rash (0.3%) Frequency Not Defined Angioedema, Vulvitis
Mechanism of Action
Activity against HSV types I and II and varicella-zoster virus is due to intracellular conversion of aciclovir to the monophosphate by viral thymidine kinase with subsequent conversion to the diphosphate and active triphosphate by cellular enzymes. This active form inhibits viral DNA synthesis and replication by interfering with viral DNA polymerase enzyme and being incorporated into viral DNA.