Retinoids are a class of bioactive compounds, which derive from Vitamin A both naturally and synthetically*. Retinol, tretinoin and many other retinoids can be found in over the counter and in prescription products to treat acne and to fight and reverse the signs of aging. They are among the most studied cosmetic ingredients being first introduced almost 50 years ago and are one of the few cosmetic ingredients for which we have extensive evidence of their efficacy.
Initially used to treat acne, patients started reporting not only an improvement of acne, but also a feeling of smoother skin and improvement of fine lines and wrinkles, which led to more and more trials to establish if and how they work.
*a more medically accurate definition for retinoids is not “derivate of vitamin A”, but molecules capable of binding to and activating retinoic acid receptors (RARs).
What are the topical retinoids available today?
Retinoids are classified in generations: first generation retinoids occur naturally in the organism, while second to fourth generation retinoids are synthetic molecules.
- First generation retinoids include Retinol, Retinaldehyde (also known as Retinal), Tretinoin (Retin-A), Isotretinoin (Accutane) and Alitretinoin.
- Second generation retinoids include Etretinate and Acitretin.
- Third generation retinoids include Adapalene, Tazarotene, Motretinide, Bexarotene, and Arotinoids
- Fourth generation retinoids include Trifarotene and Seletinoid G.
Some of these retinoids are available as systemic formulations (to be taken orally as a pill), while others exist as topical formulation (like creams, gels or serums), and others exist in both forms.
What are the indications of retinoid products?
Currently, retinoids are indicated for the treatment of acne, psoriasis, photoaging, vitamin A deficiency as well as more serious conditions such as cutaneous T-cell lymphoma and acute promyelocytic leukemia.
Not all retinoids are the same and you should ask your GP or dermatologist for some advice on which one is the best according to your needs and expectations as well as to your own characteristics such as your skin type.
Benefits of retinoids on the skin
Retinoids have many proven benefits for the skin and for this reason are a must-have in all skincare routines at all ages. They are also known as cell regulators as they are capable of regulating gene expression in the cells. Some of the evidence-based benefits are the following:
- Retinoids are capable of speeding the turn-over of skin cells
- Retinoids help unclogging pores
- Retinoids smooth the skin
- Retinoids boost collagen production
- Retinoids reduce fine lines and improve wrinkles
- Retinoids help protect from oxidative damage (free radicals)
- Retinoids address pigmentation issues such as melasma, discoloration and post-inflammatory hyperpigmentation.
- Retinoids show also anti-inflammatory and immunomodulatory
Retinoids in cosmeceuticals and skincare for the aging skin
When it comes to fight the signs of aging and sun damage, retinoids are the gold standard treatment in skincare:
- Retinol and retinaldehyde are popular ingredients in cosmeceutical preparations: they do not require prescription and are less irritating to the skin compared to other retinoids, while still producing improvement against skin aging.
- Retinyl Esters, such as retinyl -palmitate, -propionate, -acetate, are also very common in cosmetics, but their activity on the skin is limited when compared to retinol and they may show little or no effect depending on the concentration and formulation of the specific product.
- Tretinoin is a prescription-only product to treat acne but is also indicated for use in photodamaged skin. While it is more effective than retinol, it is also harsher and it is more likely to produce irritation and other side effects, especially if not used properly.
- Adapalene is an OTC product for acne. Many dermatologists indicate adapalene also for the treatment of the aging skin. It is less irritant to the skin when compared to other retinoid products of similar potency and is therefore a good alternative for those who don’t tolerate other retinoids.
Retinoids as treatment for acne
Retinoids have been used for treating acne since the ‘70s: it was the first indication for this class of products, and they are still used as first line treatment for acne. They are sometimes coupled with other treatments, such as antibiotics and benzoyl peroxide, for best results.
Topical retinoids prescribed to treat acne include adapalene, tazarotene, tretinoin, and isotretinoin all available in a variety of concentrations. The only oral retinoid prescribed for acne is isotretinoin (Accutane).
Who should use retinoids?
Anyone can use retinoids regardless of gender or age (excluding pregnant women, more on that in the warnings paragraph). They are a great addition to any skincare routine thanks to the many benefits they have. Although retinoids are often marketed as an anti-age product, this doesn’t mean they are just for the older adults: it is one of the best treatments for preventing the signs of aging skin and to have a smooth skin with a healthy glow, and there is no age restriction on it.
How long before visible effects?
Different retinoids, different concentrations and different formulations account for great variability on when results will start to be visible. Stronger concentration and prescription-only products may lead to visible results in as little as 8 weeks but are also more aggressive and may irritate the skin. Whatever the product, it takes consistent use to achieve good results.
As a general timeline with daily use of an OTC formulation:
- After one month, you may already experience a smoother skin
- After 2-4 months your complexion will be brighter and hyperpigmented spots or other pigmentation issue will be fading away.
- After 4 months lines and wrinkles should start to look better too, although it takes 6 months for more noticeable results thanks to the boost in collagen production.
It you want immediate and substantial results though, you may want to go for a consultation with a dermatologist or cosmetic surgeon: lasers, radiofrequency, ultrasounds, fillers or Botox are some of the minimally invasive and non-invasive options that may be a better choice for you; you can’t expect a miracle from a cream or serum. But if you’re in for the long run, want to improve your skin and prevent aging, then retinoids are one of the best ingredients out there!
Warnings, precautions and side effects
Oral retinoids should be avoided during pregnancy due to the increased risk of birth defects, known overall as Fetal Retinoid Syndrome, and of miscarriage. Although there is no evidence that topically applied retinoids increase the systemic levels of retinoic acid, it is still better to play it safe and avoid products containing retinoids during pregnancy: the best and safest course of action is to stop using retinoids for at least one month before conception.
Even though for males there is no evidence of sperm abnormalities following retinoid use, it is still sometimes recommended for those actively looking to have a child to avoid systemic retinoids.
Those with a more sensitive skin may want to start with low concentrations and go up from there: start by applying the product only once or twice a week and increase the frequency if you don’t feel any irritation. Another method to limit the aggressiveness of retinoids is to mix it with or layer it on top of the moisturizer or the eye cream.
Although retinoids do not cause photosensitivity (it’s a myth!) the fact that they enhance the turn-over of skin cells and peel off the top layer of the skin which is made of dead keratinocytes, may increase the chances of sunburns: a broad-spectrum SPF 30 or more is always advised, not only when using retinoids, to protect from UV rays; moreover, you are using a product also to reverse the signs of photoaging, you may want to protect your skin against it as well.
Common side effects of retinoids include dryness, irritation, redness, itching and scaling.
S Sekula-Gibbs, D Uptmore – Journal of the American Academy of Dermatology, Mar 2004
- Retinoids in cosmeceuticals.
O Sorg, C Antille – Dermatologic Therapy, Sep 2006
- Why Topical Retinoids Are Mainstay of Therapy for Acne.
J Leyden, L Stein-Gold – Dermatology and Therapy, Sep 2017
- Retinoids in the treatment of skin aging: an overview of clinical efficacy and safety.
S Murkherjee – Clinical Interventions in Aging, Dec 2006
- Fitzpatrick’s Dermatology, 9th Edition
S Kang – McGraw-Hill, 2019
- International Textbook of Aesthetic Surgery
N Scuderi – Springer, 2016
- The Art of Aesthetic Surgery – Principles and Techniques, 2nd edition
F Nahai – CRC Press, 2010
- Daily Routine in Cosmetic Dermatology
MC Almeida Issa, B Tamura – Springer, 2017
- American Academy of Dermatology (AAD)
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