Trentinoin heals from the inside out, absorbing deep within skin to attack acne at the source, stimulate collagen production, and lighten scars and blemishes by inhibiting the production of pigmentation. The result? Clearer, brighter, smoother skin. You may need to use this cream consistently for 6 weeks to 3 months in order to fully experience results. In some cases, acne will temporarily get worse during the course of treatment. This is common and treatment should continue as directed.