I have had recurrent cutaneous herpes for 30 years. Am 70 yr old, healthy, good immune system. Recently my dr has prescribed famciclovir,500mg 2 tabs,, 12 hours apart, total of 4 tabs. The first time it worked well the last two times, it stopped the progression but then 2 days later I had another herpes lesion in a different place. I have never had a second lesion occur right after the first one. What med and dosage should I use. Thank you