Probably a bit late for you now, but as a model my dermatologist would give me a prescription for Predisone to take if I was having a breakout before a shoot. You need to take it a few days in advance. Everyday I use Benzac A/C to prevent and cure. You could also go to the derm's office and have cortizone shot into your pimple if it's bad and that will clear it up in a day or two, but at a price of $50 atleast. If it's a professional shoot the photographer can airbrush it out as they do with so many pictures!