Is it safe to apply vitamin C serum while being on Accutane?

Thank you for your question. It is recommended while on Accutane to avoid using a lot of products as your skin will be overly dry and sensitive due to the medication. We highly recommend to moisturize heavily and use sunscreen daily. You could start laser treatments such as Genesis, VBeam or laser toning laser to help with the post-inflammatory hyperpigmentation and redness while on Accutane; these will help to diminish the appearance of scarring. Please keep in mind the use of these lasers depend on your skin type in order to prevent further scarring and provide an effective result. Vitamin C serum is a great product to use daily and skin brightening products can be effective with PIH, but while on Accutane it is best to hold off to avoid further irritation to the skin. Once you're close to being done the course of Accutane you could look into products that have Kojic acid or Arbutin which are not as irritating as Hydroquinone to treat any pigmentation that may still be left. 
I hope this helps.
Regards,
Sheetal Sapra, MD, FRCPC