If you have ever had a cold sore or fever blister, you must take an anti-viral pre-procedure. Your physician should prescribe Valtrex, Famvir or Zovirax. Herpetic outbreaks usually occur on the 3rd day post procedure and taking antivirals will lessen your chance of an outbreak. If you do experience a herpetic outbreak, you will lose the implanted pigment color in the area of the outbreak.