tell your doctor and pharmacist if you are allergic to acyclovir (Zovirax), valacyclovir, or any other drugs. tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially cimetidine (Tagamet), probenecid (Benemid), and vitamins. tell your doctor if you have or have ever had kidney or liver disease, problems with your immune system, human. Acyclovir remains the gold standard in the treatment of herpes virus infections, mainly due to the emerging of the new delivery systems improving considerably its bioavailability. The analogues of acyclovir, especially their esters, characterized by significantly higher bioavailability and safety, m ….