What are topical retinoids?

Topical retinoids are creams, lotions and gels containing medicine derived from Vitamin A. These compounds result in proliferation and reduced keratinisation of skin cells independent of their functions as a vitamin.

Many brand-name creams containing the retinoids retinol and retinaldehyde can be obtained over the counter at pharmacies and supermarkets.

The more potent topical retinoids available on prescription are:

• Tretinoin
• Isotretinoin
• Adapalene
• Alitretinoin.

Adapalene gel has received approval from the FDA in the USA for over-the-counter use of acne treatment in patients 12 or older (July 2016). It is also available to treat acne in combination with benzoyl peroxide.

What are topical retinoids used for?

Tretinoin, isotretinoin and adapalene are used for:

• Mild to moderately severe acne. It may take six weeks or longer before improvement occurs. They may also reduce the severity of subsequent acne scarring and can be used to reduce the severity of existing scarring [1].
• Sun damage (photoageing). If used long term (> 6 months), they may reduce fine wrinkles, freckles, solar lentigines, solar comedones, and actinic keratoses.
• Melasma, as a component of bleaching cream.

Alitretinoin gel is used to treat Kaposi sarcoma.

Do topical retinoids have any side effects?

Topical retinoids can irritate the skin, especially when first used in people with sensitive skin, resulting in stinging. Excessive use results in redness, swelling, peeling and blistering in treated areas. It may cause or aggravate eczema, particularly atopic dermatitis.

By peeling off the top layer of skin, they may increase the chance of sunburn. Irritation may also be aggravated by exposure to wind or cold, use of soaps and cleansers, astringents, peeling agents and certain cosmetics.

Some people have reported a flare of acne in the first few weeks of treatment, which usually settles with continued use.

Retinoids taken by mouth may cause birth deformities. Manufacturers recommend that topical retinoids are not used in pregnancy or breastfeeding as negative animal studies are not always predictive of human response. A systematic review did not show an increase in deformities in babies born after first-trimester exposure to topical retinoids.

Dryness due to topical retinoid

How to use topical retinoids

Follow these instructions carefully.

• Be cautious if you are using other topical acne treatments – ask your doctor if you should stop these.
• In general, a cream is less irritating than a gel. If there is a choice, start with a lower concentration product.
• Use your topical retinoid on alternate nights at first. If you have sensitive skin, wash it off after an hour or so. If it irritates, apply it less often. If it doesn't, try every night, and if possible twice daily. In most people, the skin gradually gets used to it.
• To reduce stinging, apply it to dry skin, that is, 30 minutes or longer after washing.
• Apply a tiny amount to all the areas affected, and spread it as far as it will go.
• Don't get it in your eyes or mouth.
• Apply sunscreen to exposed skin in the morning.
• Wear your usual make-up if you wish, and use gentle cleansers (avoid soap) and apply non-greasy moisturisers as often as required.
• If you have acne, choose oil-free cosmetics.
• If your skin goes scarlet and peels dramatically even with cautious use, the retinoid may be unsuitable for your sensitive skin.
• Tolerance to topical retinoids often develops over time.