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The Definitive Guide to Retinoids
Retinoids are the most researched and effective group of ingredients in skincare. They range from gentle over-the-counter serums, creams or gels to potent prescription . The reason retinoids are so popular is because of their broad range of actions including treating acne, fading hyperpigmentation and softening the fine lines and texture changes of ageing skin. The only catch is that there are so many different types of retinoids and they vary enormously in strength. In fact, choosing the wrong one for your skin is all too common and the reason people either see no results or give up due to irritation. This guide explains what retinoids are, how they work and their uses. We compare the different types of retinoids in terms of strength and what they treat. Learn how to choose between them and .
What are Retinoids?
Retinoids are a family of compounds . They all do broadly the same job in the skin, but they differ in potency Birthmarks and blemishes (just click for source) how many steps it takes them to work. This affects their effectiveness, side effect profile and whether you need a prescription. It helps to split retinoids into two groups:
One thing to clarify is that all too often when people say “retinoid” they often mean the prescription kind. When they say “retinol” they usually mean the milder over-the-counter kind. However, this isn’t actually the case. Retinol is just the basic form of Vitamin A and is the most commonly available over-the-counter. All retinoids are derivatives of Vitamin A. So everything else that isn’t Retinol is a retinoid.
How Do Retinoids Work for Skin?
Every retinoid ultimately works by turning into the same thing; retinoic acid (aka ). This is the only form the skin can actually use directly. Retinoic acid binds to receptors in your skin cells and changes how they behave. It speeds up , collagen production and helps unclog pores. This is what makes the whole family effective across acne, pigmentation and ageing.
The difference between the retinoids comes down to how far each one sits from that active form. The weaker, over-the-counter retinoids have to be converted by the skin in a series of steps before they can work. Each step loses some along the way, which is why a retinyl ester (three steps away) is far weaker than retinaldehyde (one step away). Prescription tretinoin skips the queue entirely, because it is already retinoic acid. and tazarotene are synthetic retinoids that also bind the receptors directly without needing conversion. This is the single most useful thing to understand about retinoids. The fewer conversion steps, the more potent and the . However, it also makes it more likely to irritate the skin.
The Retinoid Strength Ladder
The retinoid runs in a fixed order. Retinyl esters convert to retinol, retinol converts to retinaldehyde and retinaldehyde converts to retinoic acid. Because potency tracks so closely with how close each retinoid is to retinoic acid, the family forms a clear ladder from to strongest. The strength tiers (from lowest to highest) are:
is also a newer prescription retinoid which probably sits somehwere between adapalene and tretinoin. It is the only topical retinoid licensed for acne use on the body. Sitting outside this topical ladder is (the active in Accutane and Roaccutane). It is a prescription oral retinoid reserved for severe or treatment-resistant acne. Isotretinoin works throughout the body rather than just on the skin and has a number of serious possible side effects. It requires close monitoring throughout treatment.
What Do Retinoids Treat?
The reason retinoids are so widely prescribed is because they increase turn-over of skin cells which stimulates collagen building, smooths and unclogs pores. This mechanism of action can help address several of the most common skin concerns at once. Retinoids are useful treatments for:
At City Skin Clinic, retinoids (and tretinoin in particular) are among the ingredients we prescribe most often. They form the backbone of many of our custom , , and treatments.
Which Retinoid is Right for You?
With so many options, the right retinoid depends on three things. These are your skin’s sensitivity, the concern you are treating and your goals. As a general approach these are our top tips for choosing which retinoid to start on:
The most common mistake is jumping straight to the strongest retinoid available. A retinoid you can actually tolerate and use consistently will always beat a stronger one that irritates the skin. This can cause skin barrier damage, post-inflammatory hyperpigmentation and even drive you to give up.
How to Use Retinoids & the Retinisation Period
Retinoids reward and consistency and they punish impatience with irritation. one you use, the principles are the same. Start on the lowest strength that makes sense for your skin, apply it only two or three times a week at first, and build up the frequency as your skin adjusts. Use a pea-sized amount for the whole face at night, and always follow with a daily . This is because all retinoids make the skin more sensitive to UV damage.
The first few weeks are where most people struggle. As the retinoid speeds up cell turnover, it can trigger a period of dryness, redness, flaking and sometimes a temporary in breakouts. This adjustment period is called retinisation and the breakout part is . These are common things people can encounter and not a sign that the treatment is failing. This period usually settles within 4 to 6 weeks, and it is worth knowing how to tell . Supporting your with a good moisturiser through this phase makes a real difference, and some people prefer to to buffer it and reduce irritation. If you are still struggling with adapting after a couple of months, our post on covers the usual reasons.
Also, a word on combining retinoids with other actives. Retinoids pair well with some ingredients and clash with others, so it is worth knowing before layering them with acids or other treatments.
Retinoid Side Effects & Safety
Retinoids are powerful, and most people experience some side effects, especially early on. The good news is that the common ones are and tend to ease as the skin builds tolerance. The typical side effects are:
There is also a persistent myth worth addressing. The of a retinoid does not determine its results so much as your ability to use it consistently. This is also why retinol was rather than an outright ban.
Who Cannot Use Retinoids?
Generally speaking, retinoids suit most people with proper and approriate use. However, as with anything in life, they’re not for everyone. Below are some of the situations where you should either avoid or be more cautious:
How to Get Prescription Retinoids in the UK
Over-the-counter retinoids like retinyl esters, retinol and retinaldehyde are freely available in cosmetic products throughout the UK. However, prescription retinoids are a different matter. You can only get them through a doctor or other prescriber who has assessed your skin and decided they are safe and appropriate for you. Any website or clinic selling prescription retinoids without a consultation is not a legitimate source. Historically this meant an in-person dermatology appointment. Now you can also through a number of clinics which offer online consultations and treatment if appropriate.
At City Skin Clinic, we believe skincare should be personal. We use topical retinoids like alongside other actives where appropriate following an online consultation with one of our . They will review your skin, and medical history to create a bespoke treatment plan suitable for your needs. You can read more about our treatments for , , and , or to start your to great skin today.
This article is for general information and does not constitute medical advice. Prescription retinoids are prescription-only medicines and should be used only under the supervision of a qualified prescriber. Always read the patient information leaflet and report any suspected side effects to the MHRA via the Yellow Card scheme.
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