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Tretinoin and retinol: what is the difference?

A guide to this prescription retinoid and how it differs from retinol

Tretinoin is a prescription retinoid that has been used in dermatology since the 1970s. In the UK it is licensed for the treatment of acne.

This article explains what tretinoin is, how it differs from the retinol in cosmetic skincare, its side effects, and who should not use it.

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What is tretinoin?

Tretinoin, also known as all-trans retinoic acid, is a derivative of vitamin A. It belongs to a class of compounds called retinoids, which play an important role in regulating skin cell growth and turnover.

Unlike over-the-counter retinol products, tretinoin is a prescription-only medicine in the UK. This means it can only be obtained following a consultation with a qualified healthcare professional, such as a doctor or prescribing pharmacist.

How does tretinoin differ from retinol?

Tretinoin and retinol are often confused, but they work differently.

Retinol, found in many cosmetic skincare products, is a precursor to retinoic acid. When applied to the skin, it must be converted through a two-step process before it becomes active. This makes retinol gentler but also less potent.

Tretinoin is already in its active form, retinoic acid, so it does not require conversion. This allows it to work more directly, but it also means it can cause more irritation, particularly when first starting treatment.

How does tretinoin work?

Tretinoin works by binding to specific receptors in skin cells, influencing gene expression and cellular behaviour. Because it is already in its active form, it begins working as soon as it is absorbed, unlike retinol, which must be converted by the skin first.

What the research looks at

Tretinoin has been studied in clinical trials over several decades, mainly in acne and in skin changes caused by long-term sun exposure (photoageing). In acne it increases the turnover of skin cells, which helps stop pores becoming blocked. In sun-damaged skin, studies have looked at its effect on collagen in the deeper layers of the skin.

Whether it is suitable, and what it might do for a particular person, depends on the skin condition, medical history and how the skin tolerates it. That is a decision for a prescriber after an assessment.

What conditions is tretinoin used for?

Tretinoin is licensed in the UK for the treatment of acne. A prescriber may sometimes consider it for other skin conditions, based on an individual assessment.

Retinol and other cosmetic retinoids

Skincare products containing retinol, retinaldehyde or retinyl esters are sold as cosmetics, not medicines. They do not need a prescription, and they are not tested or regulated in the same way as prescription medicines.

What should you expect when using tretinoin?

If tretinoin is prescribed for you, it’s important to understand that results take time and there is typically an adjustment period.

Initial side effects Many people experience some degree of dryness, peeling, redness, or sensitivity when they first start using tretinoin. This is sometimes referred to as the “retinisation” period and usually improves as the skin adapts over several weeks.

Gradual improvement Visible improvements are generally not immediate. Depending on the condition being treated, it may take several weeks to a few months of consistent use before changes become noticeable.

Sun sensitivity Tretinoin can make the skin more sensitive to ultraviolet light. Daily use of a broad-spectrum sunscreen is strongly recommended during treatment.

Application Tretinoin is typically applied once daily in the evening to clean, dry skin. Your prescriber will advise on the appropriate strength and frequency for your situation.

Is tretinoin suitable for everyone?

Tretinoin is not appropriate for all patients. There are certain circumstances where it should not be used or where caution is required:

Pregnancy and breastfeeding Tretinoin should not be used during pregnancy due to potential risks to the developing baby. Women who are pregnant, planning to become pregnant, or breastfeeding should inform their healthcare provider before starting treatment.

Sensitive skin conditions Patients with eczema, rosacea, or very sensitive skin may find tretinoin too irritating and may require alternative approaches.

Other medications Certain other topical treatments, such as benzoyl peroxide or products containing alpha hydroxy acids, may increase irritation when used alongside tretinoin. It’s important to discuss your current skincare routine with your prescriber.

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Tretinoin and other treatment options

Tretinoin is one of several options available for managing skin concerns. Depending on your individual needs, a healthcare professional may recommend alternative or complementary treatments, which could include:

  • Other topical retinoids (such as adapalene)
  • Topical or oral antibiotics for acne
  • Azelaic acid for pigmentation or mild acne
  • Chemical peels or other in-clinic procedures
  • Combination formulations tailored to your skin

The most appropriate approach will depend on your skin type, medical history, the condition being treated, and your personal preferences.

Why medical supervision matters

Because tretinoin is a prescription medicine, it should only be used under the guidance of a qualified healthcare professional. They can assess whether tretinoin is appropriate for you, recommend the right formulation and strength, and monitor your progress over time.

Self-treating with prescription medicines obtained without proper consultation, for example from unregulated online sources, carries risks including incorrect dosing, counterfeit products, and lack of appropriate medical oversight.

Considering your options

If you have a concern about your skin, such as acne, pigmentation or the effects of sun damage, the first step is to speak with a healthcare professional who can assess it and explain the options. Those may or may not include a prescription medicine.

At Waterfront Private Hospital, our dermatology team see patients with skin concerns and talk through the options that may suit them.


This article is intended for general information only and does not constitute medical advice. Treatment suitability varies between individuals. Always consult a qualified healthcare professional before starting any new treatment.