Tretinoin is the acid form of vitamin A and is also known as all-trans retinoic acid. It is a drug commonly used to treat acne vulgaris and keratosis pilaris. It can also help slow the signs of aging on skin as well as masking stretch marks.It is marketed in the United States under the brand names Retin-A, Avita and Atralin. It is a very effective way  to clear up zits and pimples, but it is important to follow doctor’s instructions when using it. ebiochem.com

After the repeated application of Tretinoin, the outermost skin layer (stratum corneum) thins. At the same time, the cells in the epidermis level are stimulated to produce a thickened epidermis layer. Through this stimulation, collagen production and cellular growth in the dermis layer also increase. Typically, benefits are fully evident after seven weeks of proper application. Treatment must be maintained in order to continue to reap the benefits of Retin-A.ebiochem.com

When a dermatologist prescribes tretinoin, it is important for the patient to understand its use. Patients must introduce their skin to  the drug gradually. Patients should understand that changing the application dosage to more frequent applications can result in damage to the skin.ebiochem.com