網上搵:
Retinol is a much slower active ingredient than tretinoin. It can take up to six months or more to see real results with retinol whereas you’ll usually see results within a few weeks with tretinoin. While it is often added to over-the-counter acne treatment creams, it is not the active ingredient in acne treatment. It is used primarily for its anti-aging properties. For acne treatment, tretinoin is usually the go-to ingredient.