When do I incorporate retinol - before the maysama serum or after my LED Therapy session?

Retinol, Retinal or Tretinoin should always be applied after your LED Light Therapy treatment. Retinol and other Vitamin A derivatives can increase sensitivity to light which can increase skin sensitivity or, in some cases, lead to skin irritation. Light exposure can also degrade Vitamin A, so always best to use your Vitamin A serum after your LED Therapy and not before.