Do I have to use sunscreen with my Face-Rx medication? June 12, 2020 05:42 Updated Yes. Sunscreen is crucial when using all Face-Rx treatments, as the medication could make your skin more sensitive to the sun. Related articles Can I undergo any facial procedures while using Face-Rx treatments? Can I use this anywhere on my body? How do I apply the treatment? I am red, itchy, and experiencing side effects. What do I do? What is tretinoin?