Interesting situation. I doubt you would infect your hairstylist with herpes through the pins she puts in her mouth. However, if you are concerned, you may wish to consider taking a higher dose for a few days before your appointment, say 500 mg three times a day for three days. You may wish to talk with your doctor about that. That should go a long ways toward keeping the virus well under control. And it will make you feel better, I suspect.