Acyclovir is used for individuals detected with shingles (herpes zoster), genital herpes and chickenpox. Its results are based upon quiting the spread of the herpes virus, which indicates it does not treat the disorder and does not avoid other individuals from obtaining the infection. Listen to the instructions of your physician extremely thoroughly as the duration of therapy and dosing timetable could be various for various individuals. You might be required to take acyclovir for up to a year. Being sensitive to acyclovir and valacyclovir is a direct contraindication for taking this medicine.