How do you use Obagi-C Rx?
How do you use Obagi-C Rx? Obagi-C Rx System — Product Detail Apply to your wet face and rinse with lukewarm water. A patented formulation combining 10% professional strength Vitamin C with prescription strength 4% hydroquinone to brighten and help even skin tone. Apply evenly to your face and massage gently into skin, avoiding eye area. How long does Obagi-C last? Vitamin C serums like this one have a two-year shelf life unopened, and once you open it you should use the product within 6-9 months for optimal benefit. The pH of Obagi Professional-C Serum 20% is 2.0 - 2.4....