Both Retin-A (tretinoin) and Retinol are synthetic forms of topical Vitamin A. It has been recognized for several decades that Vitamin A plays an important role in maintaining skin health. Vitamin A is important in maintaining the skin's turnover and maturation---however, too much oral Vitamin A can be severely toxic to the skin, as well as to the eye and other organs. Therefore, forms of topical Vitamin A have been developed to treat a variety of skin disorders, including acne, psoriasis and the effects of aging.
Retin-A (tretinoin) was the first Vitamin A product developed specifically to fight comedones (blackheads and whiteheads). It does so by improving the way the plugged scaly skin in the blocked pores mature, thus forming a more normal, unblocked pore. Dermatologist call this improvement in the way the pores of the oil (sebaceous) glands mature, an improvement in "differentiation" of the pores, thus preventing the accumulation of trapped oil and bacteria. Retin A is usually used over the entire face (except the eyes and lips) to prevent new comedones and pimples.
Because Retin-A thins the dead outer layer of the skin (called the stratum corneum), using Retin-A can make the skin slightly more sensitive to the sun, as well as to other harsh environmental exposures. Retin-A is usually applied at night, and often the patient is advised to start slowly, with only 2-3 applications per week in the beginning to avoid irritation.
When using Retin-A, it is important to be patient, as the effects may take months to become noticeable. It is also very important to only use Retin-A under your health care providers direction. Do NOT use Retin-A if you are pregnant, think you might be or become pregnant or nursing. Also remember to use your sunscreen!