Retanoic acid can thin the skin therefore acts as a super exfoliant, which is great for acne, vitamin A also encourages collagen production due to increased rate of cell turnover-great for aging skins, however over use and not using sun screen can cause irritation due to the breakdown of the skins natural barrier. Used properly it is very effective.
Infomation from wikepedia:
"All retinoid forms of vitamin A are used in cosmetic and medical applications applied to the skin. Retinoic acid, termed Tretinoin in clinical usage, is used in the treatment of acne and keratosis pilaris in a topical cream. An isomer of tretinoin, isotretinoin is is also used orally (under the trade names Accutane and Roaccutane), generally for severe or recalcitrant acne.
In cosmetics, vitamin A derivatives are used as so-called antiaging chemicals- vitamin A is absorbed through the skin and increases the rate of skin turnover, and gives a temporary increase in collagen giving a more youthful appearance.When used, dryness of the affected skin may occur. More sensitive patients may also experience redness, scaling, itching, and burning. It is best to gradually increase the frequency and amount of tretinoin application to allow your skin to adjust. Heed your doctors advice when beginning a round of treatment.
This product increases the risk of extreme sunburn. Application of sunscreen while using tretinoin is strongly recommended. If sunscreen is not applied, there is a minimal evidence of an increase in incidence of skin cancer.
Because usage of tretinoin may cause thinning of the skin, it is strongly recommended that patients who are using the drug abstain from hair removal waxing. The wax will, when removed, pull off the top level of epithelium (skin) with it, leaving a red, inflamed, sore, and unattractive mark for several days. If you wish to have hair removal treatments performed while using tretinoin, opt for tweezing or threading (epilation). The recommended timeframe to wait for a waxing treatment after using tretinoin varies from source to source; anywhere from 5 days to 3 months have been reported. Speak to your aesthetician and dermatologist to discuss the best option for hair removal during or after tretinoin use."
I use a retinol eyecream from roc and it is excellent. Not sure about the best stretch mark creams- I would love to find a good one though! I have them just from normal growth at puberty which seems unfair as I have never been over weight. I have always believed there is no cure once they have turned white (I never noticed mine being red-has anyone else seen this stage?) as the damage is permanent (I'd love to be wrong!) you can check out this link:
http://en.wikipedia.org/wiki/Stretch_marks
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