Acyclovir is used for people diagnosed with roof shingles (herpes zoster), genital herpes and chickenpox. Its impacts are based upon stopping the spread of the herpes infection, meanings it does not heal the problem and does not stop various other people from getting the infection. Pay attention to the directions of your medical professional very carefully as the period of therapy and dosing timetable might be various for different individuals. You could be needed to take acyclovir for up to a year. Being sensitive to acyclovir and valacyclovir is a direct contraindication for taking this medication.