What is cosmetic?
A cosmetic is defined as a topically applied product that is used to beautify, cleanse or protect the hair, skin, teeth or complexion.
In essence, a cosmetic should not contain any active drug ingredient that may affect the structure or function of the skin. The division of cosmetics and drugs is not always clear as there are many products available that have two intended uses, for example, an antidandruff shampoo is a cosmetic because it is intended to cleanse the hair, but it also contains a drug to treat the scalp and dandruff. Such products must comply with the requirements for both cosmetics and drugs.
Cosmetics can be broadly divided into the following groups.
- Facial make-up: eye make-up, lipstick, blushes, foundation
- Nail care: varnish, remover, artificial nails
- Skincare: cleanser, moisturiser, toner
- Haircare: shampoos, hair colour, dye, regrowth treatment
- Oral care: toothpaste, mouthwash
- Body cleansers: soap, bath additives, shower gel
- Shaving: shaving foam/cream, aftershave
- Fragrances and perfumes
- Deodorant: deodorant, antiperspirant
- Sun protection: sunscreen
Cosmetics standard authorities
Countries around the world have in place regulatory standards that ensure these products are safe for the workers handling them, the environment, and for use by consumers.
Who gets contact reactions to cosmetics?
It is estimated that on average, women are using at least seven types of cosmetic each day and reactions to these products are quite common. Although the prevalence of cosmetic allergy in the general population is unknown, several studies suggest that up to 10% of the population will have some type of reaction to a cosmetic throughout a lifetime. This figure may be much higher as many mild reactions occurring at home are self-diagnosed and often self-treated.
What kind of reactions can occur?
Cosmetics can produce a range of adverse reactions.
- A local burning sensation, tingling, itching may occur within minutes to about 1 hour after contact with the skin.
- Swelling and redness (wheal and flare) may be seen.
- The rash usually resolves by itself within 24 hours of onset.
- Irritant contact dermatitis accounts for 80% of all cases of contact dermatitis.
- This can occur in anyone, but people with atopy are more prone to irritant dermatitis than non-atopics.
- Dermatitis usually begins as patches of itchy, scaly skin or red rash, and can also present as blisters that ooze.
- For strong irritants, a reaction may occur within minutes or hours of exposure.
- For weaker irritants, it may take days or weeks of continued exposure before symptoms appear.
- Allergic contact dermatitis occurs when a person’s immune system is sensitised to an allergen (the person is allergic to a specific ingredient).
- A rash usually develops more than 12 hours after contact with the allergen and peaks about 48 hours after exposure.
- Symptoms of allergic contact dermatitis include redness, swelling, intense itching and urticated erythema.
- The face, lips, eyes, ears and neck are the most common sites for cosmetic allergy.
- Photocontact dermatitis is caused by the interaction of sunlight with an ingredient in the cosmetic.
Some people may develop more than one type of reaction. For example, an atopic individual may be prone to irritant contact dermatitis, which in turn increases their likelihood of allergic contact dermatitis, as their skin barrier function is weakened and sensitised to the allergen.
It is possible for a cosmetic allergy to develop even after years of using a cosmetic without previous problems.
Contact allergic dermatitis to cosmetics
What are the allergens in cosmetics?
The range of cosmetics is vast, so the pool of allergens is infinitely huge. The groups of allergens that appear to most frequently cause cosmetic allergy are fragrances, preservatives, and paraphenylenediamine (PPD) found in hair dyes.
- There are more than 5000 different fragrances used in cosmetics and skincare products.
- They are present in most types of cosmetics including perfumes, shampoos, conditioners, moisturisers, facial cosmetics, and deodorants.
- Fragrances are the most common reason for contact dermatitis from cosmetics.
- 70–80% of fragrance allergy can be picked up by patch testing with Fragrance Mix and Balsam of Peru
- Cosmetic labelled “unscented” does not mean fragrance-free; some unscented products may contain a fragrance to mask another chemical odour. Products should be labelled ‘fragrance-free’ or ‘without perfume’ to indicate no fragrances have been used.
- Preservatives are the second most common cause of contact allergic dermatitis to cosmetics.
- Cosmetics that contain water have a preservative in them to prevent bacterial or fungal growth.
- Some of the preservatives most commonly found in cosmetics include:
Paraphenylenediamine in hair dye
- Paraphenylenediamine (PPD) is the third most common ingredient after fragrances and preservatives to cause allergic contact dermatitis.
- It is used widely in permanent hair dyes because it results in a natural colour.
- Reactions to PPD may be mild and involve dermatitis to the upper eyelids or rims of the ears or may be more severe with swelling of the scalp, face and more widely.
- New derivatives of PPD have a lower risk of causing an allergy.
Other allergens used in cosmetics that can cause cosmetics allergy include:
How is cosmetic allergy diagnosed?
Cosmetic allergy is diagnosed by performing patch tests. A diagnosis may involve testing against some different chemicals due to the many potential allergens in cosmetics, as well as the person’s cosmetics applied as-is. See individual contact allergens for patch testing recommendations.
An open application test may also be recommended.
Patch tests revealing multiple contact allergies to fragrances
What is the treatment for cosmetic allergy?
Contact dermatitis should clear rapidly once the cosmetic allergen is removed. Over-the-counter creams and ointments containing mild topical steroids, such as hydrocortisone cream, may be used to help control itching, swelling, and redness. A prescription steroid cream may be required for severe reactions, as well as an antibiotic for a secondary bacterial infection. Bland emollients such as cetomacrogol cream can be used to soothe and relieve dryness.
Prevention of cosmetic allergy
The best way to prevent contact allergic dermatitis to cosmetics is by avoiding all products that contain the allergen.
- Read the list of ingredients on all cosmetic products to identify if they contain a relevant allergen.
- Test new cosmetics placing a small sample of the product on the inner wrist or elbow and observe for 24–48 hours.
- Choose products with few ingredients to minimise potential allergens.
- Apply perfume to clothing rather than to the skin; allow the perfume to dry before putting on the clothes.
- Look for products that are hypoallergenic, fragrance-free and non-comedogenic. However, be aware that these may still cause reactions.
Author: Vanessa Ngan
Source: Allergic Reactions to Cosmetics