Author: Vanessa Ngan, Staff Writer, 2012.
A cosmetic is defined as a topically applied product that is used to beautify, cleanse or protect the hair, skin, teeth or complexion. 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.
In essence, a cosmetic should not contain any active drug ingredient that may affect the structure or function of the skin. However, 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.
As you can see cosmetics play an important part in our daily life. It is estimated that on average women are using at least seven types of cosmetic each day, so it is not surprising that 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 over the course of a lifetime. This figure may be much more as many mild reactions occurring at home are self-diagnosed and often self-treated.
An allergy to a cosmetic can produce a range of reactions.
Some people may suffer from more than one type of reaction. In particular, atopic individuals are more 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.
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.
Other allergens used in cosmetics that can cause cosmetics allergy include:
Cosmetic allergy is diagnosed by performing special allergy tests, called patch tests. Diagnosis may involve testing against a number of different chemicals due to the many potential allergens that cosmetics are made up of, as well as the person's own cosmetics as is. See individual contact allergens for patch testing recommendations.
An open application test may also be recommended.
Contact dermatitis should clear rapidly once the cosmetic allergen is removed. Over-the-counter creams and ointments containing mild topical steroids, such as hydrocortisone 0.5–2.5%, may be used to help control itching, swelling, and redness. In more severe cases, a prescription steroid cream may be required, as well as antibiotic medication if the skin becomes blistered and infected. Bland emollients such as cetomacrogol cream can be used to soothe and relieve dryness.
If you have a cosmetic allergy the best way to prevent any problem is by avoiding all products that contain the allergen you are sensitive to. Some steps you can take to reducing cosmetic allergy reactions include:
Your dermatologist may have further specific advice, particularly if you are highly sensitive to particular cosmetic allergens.
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