What is Tretinoin?

Tretinoin is a biologically active form of vitamin A that is extensively proven in treating acne and sun-induced skin aging.

Tretinoin Brand Names

Tretinoin is the active ingredient in the prescription products Retin-A and Renova. In the United States, tretinoin is available only by prescription. Non-prescription beauty creams may contain retinol, which is a relative of tretinoin but does not have the same efficacy.

Retinoid types

Retinoid is the umbrella term for vitamin A and its derivatives. From weakest to strongest, retinoids are:

Retinyl palmitate

Retinyl palmitate is a common OTC. It is the weakest but the safest form of vitamin A. It is suitable for daily use, with very little irritation, but is generally not used in high enough concentrations to significantly impact skin concerns. Many products labeled “retinol treatments” use retinyl palmitate instead, so check the ingredients list.

Hydroxypinacolone retinoate

Hydroxypinacolone retinoate (HPR), found in “Granactive Retinoid” mixes, might be an effective acne treatment and anti-aging ingredient. It is a generally well-tolerated OTC retinoid that should be easy to introduce. However, most clinical studies combined HPR with other retinoids, making it difficult to tell how significant the effects of HPR are ^8-12.

1. The Ordinary Granactive Retinoid 2% in Squalane
2. The Ordinary Granactive Retinoid 5% in Squalane
3. The Ordinary Granactive Retinoid 2% Emulsion
4. Mad Hippie Vitamin A Serum

Retinol

Retinol is a common OTC retinoid that treats acne ¹³ and has anti-aging effects ^14-19 by minimizing fine lines and wrinkles and increasing epidermal thickness. Studies have shown retinol is about 20 times weaker than prescription tretinoin ¹.
It can be a volatile ingredient that breaks down when exposed to heat, light, and air. That’s why it’s a good idea to look for products with encapsulated retinol, airless pump packaging, and opaque containers.

1. Superfacialist Anti-Aging Serum (0.01%)
2. Paula’s Choice Resist Intensive Wrinkle Repair Serum (0.1%)
3. Paula’s Choice Resist Skin Smoothing Body Treatment (0.1%)
4. Alpha Skincare Deep Wrinkle Repair (0.15%)
5. SkinPrep 0.5% Retinol (0.5%)
6. The Ordinary 0.2% Retinol
7. The Ordinary Retinol 0.5% in Squalane
8. The Ordinary Retinol 1% in Squalane
9. Paula’s Choice Clinical 1% Retinol Treatment (1%)
10. Peter Thomas Roth Retinol Fusion PM (1.5%)

Retinaldehyde

Retinaldehyde, also called retinal, is an OTC retinoid with anti-aging benefits ²⁰, increases epidermal thickness, increases elasticity, and may treat acne ²¹.

1. Avène RetrinAL 0.05 Cream (0.05%)
2. Avène RetrinAL 0.1 Intensive Cream (0.1%)
3. Mychelle Retinal Serum

Adapalene (Differin)

Adapalene is a retinoid that is OTC in the U.S. but is prescription-only in many other countries. It treats acne ^22-26 and decreases oiliness ²⁶.

Whether adapalene is an efficient anti-aging ingredient like other retinoids comes up quite often. A few studies look promising, although each has limitations, such as a lack of control or an absence of objective measurements. Unfortunately, there doesn’t appear to be enough research to give a decisive answer one way or the other, at least for the time being ^27-28.

Shop Target, CVS.

Tretinoin (Retin-A)

Tretinoin, today’s article’s subject, is a well-studied retinoid. Also known as all-trans retinoic acid, tretinoin is a metabolite of Vitamin A. It is produced in the body from other retinoids ingested, such as retinol, retinyl esters, and carotenoids. Tretinoin is prescription-only in the U.S. and most countries.
It treats acne ²⁵, hyperpigmentation ^29-36, has anti-aging effects ^29-39, minimizes fine wrinkles, and increases epidermal, dermal, and granular cell layer thickness.
Tretinoin may also reduce pore size ³⁹.

Tazarotene

Tazarotene is a prescription-only retinoid that treats acne ^{25, 41}, hyperpigmentation ^{33, 41-42}, has anti-aging effects ^{33, 41-42}, and minimizes fine lines and wrinkles.
Tazarotene is stronger than adapalene and may reduce pore size ⁴².
It is potentially more efficacious than tretinoin at treating papules and open comedones and can be used to treat psoriasis.

Isotretinoin

Topical isotretinoin is a retinoid that treats acne ⁴⁴, has anti-aging effects, minimizes fine lines and wrinkles, and increases epidermal thickness ⁴³.
It is prescription-only in most countries.

Safety

It is possibly not safe to use while breastfeeding or while pregnant!

Isotretinoin (Accutane) has teratogenic effects meaning it causes birth defects. So with an abundance of caution, medical providers also recommend avoiding tretinoin while pregnant.

Due to the poor absorption of tretinoin from the skin, studies suggest that the risk of malformations in human fetuses after topical application of tretinoin is smaller. Still, it is recommended to err on the safe side and not use tretinoin while pregnant or breastfeeding.

https://www.drugs.com/mtm/tretinoin-topical.html

Tretinoin benefits

Tretinoin is a fantastic tool that can deliver healthy-looking, beautiful skin, including a host of benefits when used correctly.

Most subjects develop a healthy-looking, so-called “tret glow,” and skin tone irregularities may even out.

Tretinoin has been shown to have scientifically proven effects on the skin:

• treating and preventing acne vulgaris;
• anti-aging effect; Tretinoin is considered the gold standard for treating and preventing fine lines and wrinkles (to an extent);
• lightening effect – anti-yellowish skin;
• PIH – brown-ish hyperpigmentation;
• treating shallow indented scarring;
• reducing oil production
• smoothing;
• tightening; Tretinoin may help reduce the appearance of pores;
• treating photodamage;
• increasing epidermal thickness;
• aid in melasma treatment;
• aid in vitiligo treatment.

Tretinoin for acne

Tretinoin helps regenerate skin cells and prevents the clogging of follicles (pores). Tretinoin helps prevent blackheads, whiteheads, and inflamed acne lesions by decreasing follicular plugging.

Acne improvement may take at least 12-16 weeks to see full benefits from tretinoin.

Tretinoin for anti-aging

Tretinoin acts by various mechanisms in skin aging to fight dark spots and wrinkles. Additionally, it has been shown to promote smoother, tighter, and fuller skin by stimulating the production of collagen and glycosaminoglycans.

Visible signs of wrinkles and some coarse wrinkles may improve by 4-6 months.

Tretinoin for hyperpigmentation

Tretinoin helps with hyperpigmentation. It decreases the darkness of brown spots by reducing epidermal pigmentation. Also, it pinkens sallow skin.

Sun-induced brown spots, mottled hyperpigmentation, and freckles may start to lighten 4-6 months after starting treatment.

Tretinoin does not help with

• reducing redness – increased vascularity means redness can increase for some;
• soothing irritation – tretinoin is one of the most irritating ingredients;
• PIE (Post-irritation erythema) – erythema is the dilation of the blood vessels. Tretinoin increases vascularity making erythema worse. If you have pale skin, this looks like redness. If you have darker skin, this can look like a “glow.”  If you’re pale, azelaic acid, niacinamide, and vitamin c are better for dealing with hyperpigmentation.

How to use Tretinoin?

Hydration is key. Read different methods on how to apply tretinoin for optimal results.

Use moisturizer both morning and night. Moisturizing before applying tretinoin can improve tolerance and does not interfere with effectiveness.[2]

Morning

1. Holika Holika Good Cera Super Ceramide Mist
2. COSRX – Advanced Snail 96 Mucin Power Essence
3. Moisturize
4. Use a broad spectrum SPF 30+ sunscreen if spending time outdoors, and avoid sunlight if unprotected.

Read more on why you should use sunscreen while on tretinoin.

Evening

1. Cleansing
2. Hydrate
3. Thoroughly moisturize
4. Let face dry
5. Apply a pea-sized amount of tretinoin to the face.
6. Rub lightly into the whole face, but avoid the eyelids.
7. Moisturize

Tretinoin purging

When starting tretinoin for anti-aging purposes, if you don’t usually have acne, you shouldn’t experience purging in the form of breakouts.
Tretinoin brings “brewing” pimples to the surface. If there’s nothing brewing, there’s nothing to purge.

If your skin is acne prone, read our in-depth guide to distinguish between breaking out from irritation and tretinoin purging.

Tretinoin peeling and flaking

When the dose and the concentration of tretinoin are low, such adverse reactions tend to be mild.

But, if irritation develops, it could be a sign that you’ve damaged your skin barrier, and you need to stop treatment until needed and moisturize frequently.

The most common side effects are:

• dry skin
• skin flaking,
• peeling
• irritation
• erythema
• redness;
• sun sensitivity (retinoids should be applied at night).

Minor side effects of the drug are usually temporary and can be treated with regular over-the-counter skin care products like facial moisturizer. You may use Aquaphor or Vaseline if irritation occurs at the corners of the mouth or eyes.

After restarting with tretinoin:

• minimize the dose – restart with smaller amounts of cream;
• use it once every 2-3 days;
• minimize the strength – use low-strength tretinoin until your skin is accustomed to the medication’s effects;
• hydrate more
• moisturize more

Tolerance usually improves with continued use in 3-4 weeks. Then you can use tretinoin nightly.

Side effects

Serious side effects of tretinoin are rare.

Serious side effects include skin discoloration, blistering, facial swelling, burning, conjunctivitis, and eye swelling. These side effects are rare and should be treated immediately by a doctor.

A small percentage of people who use tretinoin may have an allergic reaction. This can cause rashes, swelling, and difficulty breathing. These side effects are rare and should be treated immediately by a doctor.

Tretinoin and sunscreen

Sunscreen is a MUST with tretinoin. If you start tretinoin, this is non-negotiable. I probably don’t have to re-iterate, but tanning is also out of the question.

You must commit to using a sunscreen every day. Yes, even if it’s winter, even if you have dark skin, even if you don’t enjoy it. Make-up SPF is not enough.

If you can’t commit to wearing sunscreen daily, tretinoin is not for you.

Tretinoin and actives

When you’re first starting tretinoin, to avoid more irritation, stop all other actives. Morning AND night.

Unless stated otherwise by your medical provider, stop other actives at least one week before starting tretinoin. That means no:

• BHA;
• AHA;
• benzoyl peroxide;
• Vitamin C. 

You’re the expert on your type of skin and will have to decide what works for you, but please, start slow and be very gentle.

Once you’ve been using tretinoin for 6+ months, you can add these back in as needed.

Hair Removal

Skin treated with tretinoin may become very sensitive to procedures such as peels, waxing, laser, or microdermabrasion. Stop tretinoin for at least 2-3 days before receiving facial treatments. Please inform your aesthetician of your use of tretinoin before receiving these treatments.

Tretinoin users should avoid hair removal by waxing or depilation in areas where retinoids are applied. Opt for plucking, shaving, or threading instead.

References

1. Cosmetic Dermatology – Baumann
2. Adjunctive use of a facial moisturizer SPF 30 containing ceramide precursor improves tolerability of topical tretinoin 0.05%: a randomized, investigator-blinded, split-face study. JDD, 01 Sep 2012, 11(9):1104-1107
   https://europepmc.org/article/med/23135655
3. Moisturizer improves tolerability for tazarotene and does not negatively impact efficacy. Tanghetti, Emil, et al. Poster presented at 32nd Annual Hawaii Dermatology Seminar. 2008.
   https://dermatologyandlasersurgery.com/wp-content/uploads/2020/01/2008-Poster-Moisturizer-Use-Enhances-Facial-Tolerability.pdf
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   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3997205/
5. The Role of Skin Care as an Integral Component in the Management of Acne Vulgaris: Part 2: Tolerability and Performance of a Designated Skin Care Regimen Using a Foam Wash and Moisturizer SPF 30 in Patients with Acne Vulgaris Undergoing Active Treatment. J Clin Aesthet Dermatol. 2013 Dec; 6(12): 28–36.
   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3997206/
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   https://www.sciencedirect.com/science/article/pii/S0022202X15526675
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   https://europepmc.org/article/med/23135655
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