Allergen, Not An Allergen Featured

DISINFECTING BLEACH: Allergen or Not An Allergen?

Not An Allergen…But A Strong Irritant

Disinfecting Bleach

The main component of many disinfecting bleaches is sodium hypochlorite, which is not listed as a top contact allergen. However, it is a strong irritant that can cause chemical burns. Many bleaches contain other caustic ingredients which can also burn the skin by destroying its fatty tissue and oils. Specific to allergens: many disinfecting bleaches contain common contact allergens like fragrances and dyes.

That said, when pure (no added allergens), in low concentrations, and used very carefully, bleach baths are common treatments for skins that tend to develop infections due to barrier damage or steroid overuse. In addition to some steroids being allergens themselves, using steroids daily or over a long period of time can lead to several health problems as well as to an overgrowth of non-pathogens and/or opportunistic microbes such as Staphylococcus aureus. In several cases, bleach baths have been shown to improve atopic dermatitis and lessen the need for steroids. IMPORTANT: bleaches can be caustic, highly irritating, or even toxic. Sodium hypochlorite can react with many things — when exposed to sunlight, it can produce the lung irritant chlorine gas and exposure to ammonia can produce toxic chloramines. Do not start bleach baths without your physician’s approval and close supervision.

Bleaches can also contain chlorine, a strong irritant that can cause several skin problems, from rashes to acne. Bleach is also a powerful photo-allergen — exposure to sunlight and even indoor lights (from lamps as well as your TV, phone, tablet, or computer) can cause dark spots and large dark patches. This is why some individuals who work in or around pools or who use household cleaning products with chlorine develop dark patches and blotches on the face and/or other areas of exposed skin. It’s such a powerful photo-allergen that reactions can occur simply from airborne exposure, without direct contact with skin.

Lastly, when inhaled, bleaches can also irritate the mucosa to produce upper respiratory problems, rhinitis-related problems, asthma, and a recurring sore throat.

If you have a history of sensitive skin, don’t guess: random trial and error can cause more damage. Ask your dermatologist about a patch test.

To shop our selection of hypoallergenic products, visit Need help? Ask us in the comments section below, or for more privacy (such as when asking us to customize recommendations for you based on your patch test results) contact us by email, or drop us a private message on Facebook.

For more:

On the prevalence of skin allergies, see Skin Allergies Are More Common Than Ever and One In Four Is Allergic to Common Skin Care And Cosmetic Ingredients.

To learn more about the VH-Rating System and hypoallergenicity, click here.

Main References: 

Regularly published reports on the most common allergens by the North American Contact Dermatitis Group and European Surveillance System on Contact Allergies (based on over 28,000 patch test results, combined), plus other studies. Remember, we are all individuals — just because an ingredient is not on the most common allergen lists does not mean you cannot be sensitive to it, or that it will not become an allergen. These references, being based on so many patch test results, are a good basis but it is always best to get a patch test yourself.

1. Warshaw, E.M., Maibach, H.I., Taylor, J.S., et al. North American contact dermatitis group patch test results: 2011-2012. Dermatitis. 2015; 26: 49-59

2. W Uter et al. The European Baseline Series in 10 European Countries, 2005/2006–Results of the European Surveillance System on Contact Allergies (ESSCA). Contact Dermatitis 61 (1), 31-38.7 2009

3. Wetter, DA et al. Results of patch testing to personal care product allergens in a standard series and a supplemental cosmetic series: An analysis of 945 patients from the Mayo Clinic Contact Dermatitis Group, 2000-2007. J Am Acad Dermatol. 2010 Nov;63(5):789-98.

4. Verallo-Rowell VM. The validated hypoallergenic cosmetics rating system: its 30-year evolution and effect on the prevalence of cosmetic reactions. Dermatitis 2011 Apr; 22(2):80-97

5. Ruby Pawankar et al. World Health Organization. White Book on Allergy 2011-2012 Executive Summary.

6. Misery L et al. Sensitive skin in the American population: prevalence, clinical data, and role of the dermatologist. Int J Dermatol. 2011 Aug;50(8):961-7.

7. Warshaw EM1, Maibach HI, Taylor JS, Sasseville D, DeKoven JG, Zirwas MJ, Fransway AF, Mathias CG, Zug KA, DeLeo VA, Fowler JF Jr, Marks JG, Pratt MD, Storrs FJ, Belsito DV. North American contact dermatitis group patch test results: 2011-2012.Dermatitis. 2015 Jan-Feb;26(1):49-59.

8. Warshaw, E et al. Allergic patch test reactions associated with cosmetics: Retrospective analysis of cross-sectional data from the North American Contact Dermatitis Group, 2001-2004. J AmAcadDermatol 2009;60:23-38. 

9. Foliaki S et al. Antibiotic use in infancy and symptoms of asthma, rhinoconjunctivitis, and eczema in children 6 and 7 years old: International Study of Asthma and Allergies in Childhood Phase III. J Allergy Clin Immunol. 2009 Nov;124(5):982-9.

10. Kei EF et al. Role of the gut microbiota in defining human health. Expert Rev Anti Infect Ther. 2010 Apr; 8(4): 435–454.

11. Thavagnanam S et al. A meta-analysis of the association between Caesarean section and childhood asthma. Clin Exp Allergy. 2008;38(4):629–633.

12. Marks JG, Belsito DV, DeLeo VA, et al. North American Contact Dermatitis Group patch-test results, 1998 to 2000. Am J Contact Dermat. 2003;14(2):59-62.

13. Warshaw EM, Belsito DV, Taylor JS, et al. North American Contact Dermatitis Group patch test results: 2009 to 2010. Dermatitis. 2013;24(2):50-99.

Want more great information on contact dermatitis? Check out the American Contact Dermatitis SocietyDermnet New Zealand, and your country’s contact dermatitis association.

Laura is our “dew”-good CEO at VMV Hypoallergenics and eldest daughter of VMV’s founding dermatologist-dermatopathologist. She has two children, Madison and Gavin, and works at VMV with her sister CC and husband Juan Pablo (Madison and Gavin frequently volunteer their “usage testing” services). In addition to saving the world’s skin, Laura is passionate about health, inclusion, cultural theory, human rights, happiness, and spreading goodness (like a great cream!)

Allergen, Not An Allergen Featured Skin

It’s Complicated: Allergic Versus Irritant Reaction

A reaction is a reaction…isn’t it?

Yes, in that a skin reaction usually looks and feels “off.” No, in that a skin reaction can be irritant or allergic. Some substances can be irritants but not allergens (such as the iodine on the bottom right of the photo above) or allergens but not irritants (such as the lemongrass essential oil on the top left of the photo above). Always trust your dermatologist to make the diagnosis, but this is a quick overview to help you understand the difference between the two:


An irritant reaction is a form of contact dermatitis but it is not an allergic response. According to DermNet NZ, “Irritant contact dermatitis is a form of contact dermatitis, in which the skin is injured by friction, environmental factors such as cold, over-exposure to water, or chemicals such as acids, alkalis, detergents and solvents.”

Irritant reactions have a relationship with the concentration of the ingredient in a product, the frequency of your skin’s exposure it, and how long your skin is exposed to it. While a diagnosis needs to be made by your dermatologist, here are examples of what an irritant reaction might look like:

  • You use a moisturizer most of your life and experience relatively mild symptoms like dryness that you don’t think of as a reaction, but that are, in fact, mild irritant reactions. If you spread on more of the moisturizer or use it more often, you notice more dryness or possibly other symptoms like redness. If you stop using it for a while, the symptoms subside. And when you use it again, you don’t notice a problem unless you use more of it or use it more frequently.
  • Babies often get an irritant reaction from their saliva around the mouth and on the chin. The reaction goes away as they drool less as they get older.
  • Temporary burns from strong chemicals like chlorine.
  • Itching and redness after touching certain insects.
  • Dry, red, itchy skin from winter or dry, cold air.
  • An instant redness or itching after applying a certain threshold amount of a cosmetic product (in an allergic reaction, the symptoms would appear regardless of the amount applied).


An allergic reaction is a true allergy, meaning that the body has an immune response to an allergen.

You can use something for weeks, months, or years without a problem and then only later develop an allergy to it. This happens once your cells recognize a substance as foreign. After this, on repeat exposure, the allergic reaction occurs even with exposure to small amounts of the allergen (whereas an irritant reaction would require a certain threshold amount to elicit a reaction). If you are allergic to a substance or develop an allergy to it, any percentage of it for any amount of time on the skin will cause a reaction.

Irritant Versus Allergic

The percentage of an irritant or allergen (how much of it was applied or how much of it the skin was exposed to) is important in differentiating irritant and allergic contact dermatitis.

Irritants at a high concentration cause acute irritant contact dermatitis (marked swelling and blistering), such as after just a one-time exposure to a strong acid. At lower concentrations of an irritant and/or constant exposure to it, a chronic irritant contact dermatitis can develop. You might see this in the hands — the skin becomes thick and leathery — of people who work in the health, laundry, or cleaning industries from the frequent exposure to strong soaps and cleaning agents. That said, you could also actually build a tolerance to mild irritants over time.

In allergic contact dermatitis, you may be exposed to an allergen for weeks, or even most of your life, and not react to it. This changes once your skin’s T cells recognize the allergen as “foreign” or “bad,” and develop an immune response then a delayed response that continues every time you are exposed to it from that moment on. Once this immune response is set, any amount of the allergen shortly after contact with your skin will cause a reaction.

An allergic reaction can coexist with an irritant reaction. For example, dryness or redness from the frequent use of alcohol, bleaches, chlorine or other disinfecting products could be an irritant reaction. But if the products also contain fragrances, preservatives, formaldehyde or other top allergens, you might also develop an allergic reaction.

Contact dermatitis experts are the specialists to accurately identify whether the skin changes you are seeing — dryness, redness, dark patches, and other symptoms — are an irritant or allergic reaction. A patch test is important to accurately identify which substance or ingredient is causing the reaction, and patch tests can also confirm if a reaction is allergic or irritant. After you get your patch test results, you’ll know exactly what you need to avoid. And often, just simple and careful avoidance of the substance can give you relief and clarity.


Check out the other posts related to contact dermatitis:

Allergen-Not An Allergen

Get A Patch Test Or Photo-Patch Test

On Contact Dermatitis, Sensitive Skin, and Patch Testing: Interview with an Expert

Laura is our “dew”-good CEO at VMV Hypoallergenics and eldest daughter of VMV’s founding dermatologist-dermatopathologist. She has two children, Madison and Gavin, and works at VMV with her sister CC and husband Juan Pablo (Madison and Gavin frequently volunteer their “usage testing” services). In addition to saving the world’s skin, Laura is passionate about health, inclusion, cultural theory, human rights, happiness, and spreading goodness (like a great cream!)


On Contact Dermatitis, Sensitive Skin, and Patch Testing: Interview with an Expert

Is a rash a skin allergy or an irritation? What is a patch test and why would I need one? How can I prevent rashes? To get clarity, we spoke to Jenny Murase, Chair of the CAMP Optimization Task Force of the American Contact Dermatitis Society, Associate Clinical Professor at UCSF, and Director of the Patch Test Clinic at the Palo Alto Foundation Medical Group.

1) We understand that the American Contact Dermatitis Society is an organization for dermatologists who are interested in or specialize in contact dermatitis. Why is the ACDS necessary?

The ACDS provides a critical role in the dermatology and allergy community. Our society is a group of subspecialists who provide diagnostic testing for dermatitis (rash). When someone gets a rash that is chronic (lasts a long time) and recalcitrant (does not respond to therapy), it is possible that there is an external component to consider. Irritant contact dermatitis and allergic contact dermatitis are both possible. Through our patch testing, we help to uncover what could be triggers for rash. The ACDS provides dermatologists and allergists with tools to educate their patients during this testing, such as handouts describing the patient’s allergens and the Contact Allergen Management Program (CAMP) which creates a safe list of products for patients that do not contain their allergens.

2) What are some common allergens?

These include some substances in skin care products like some preservatives, fragrances, surfactants, and emulsifiers as well as hair dyes, textile dyes, metals, topical medications like antibiotic ointments or topical steroid ointments, plastics, rubbers, adhesives, among many other allergens.

3) What is a patch test and why is it useful?

Patch testing is a diagnostic test that looks for delayed hypersensitivity reactions, which means rashes on the skin that develop in response to an allergen coming in contact with the skin that the patient has developed memory immune cells to recognize and respond to. A classic example would be poison oak, where a patient is exposed and then develops a red rash within days because they have immune cells that respond to the poison oak allergen. This is different from an immediate hypersensitivity reaction mediated by histamine which results in an immediate reaction on the skin, like contact hives (urticaria) or an anaphylaxis reaction (like latex allergy, for example). Because this is a delayed reaction, it takes a few days to read the test. Patches with certain substances are placed on the back and are removed after 48 hours, with an interpretation at 3-7 days after placement to see how the patient is responding to the allergens.

4) What are some of the causes of skin allergies and what are some best practices to manage them?

I listed the causes of skin allergies in my answer for question two, and the best practice is avoidance of the allergen, if at all possible. We provide patients with a safe product list through CAMP for skin care products ranging from shampoos, soaps, moisturizers, and even laundry soap and detergents. We also provide ways to avoid non-skin care product allergens like rubber in certain rubber gloves or textile dye allergy through dye-free clothing. In addition, we provide dietary tips on how to avoid consuming some allergens that can cause a “systemic contact dermatitis,” including allergens like tocopherol, propylene glycol, balsam of peru, cobalt and nickel.

5) Is sensitive skin common or is it all hype/a trendy excuse?

Sensitive skin can mean a variety of things to patients. Someone who has had hives (urticaria) or eczema (atopic dermatitis) can feel that they have sensitive skin since their skin breaks out in rashes easily. It can also mean that they have become more and more sensitive to skin care products throughout their life by developing allergic contact dermatitis slowly over time. Diagnostic testing like patch testing can help to clarify what is driving the rash and/or the itch.

6) What is CAMP, why was it created, and how does it help patients who’ve had a patch test?

CAMP is the Contact Allergen Management Program. It was created for ACDS members in order to be able to provide a safe list of products that do not contain the allergens that the patient is allergic to or any of the cross reactants. It can be difficult to read labels if you do not know all the different chemical names and cross reactors. For example, if you tested positive to formaldehyde, you needs to avoid ingredients like Quaternium 15 and DMDM Hydantoin. CAMP takes the guess work out of finding safe products for the patient because it is easier for them to look for items on their safe list and buy those than to try to process all the possible reactions.

7) We heard there’s a new app for CAMP! Is it for me (does my dermatologist have to be a member of the ACDS), and how can I check?

In order to get access to the CAMP app, your dermatologist needs to be a member of the ACDS. CAMP will generate codes that you place into the app when it is downloaded to the phone, and using these codes, a list of products that do not contain your allergens can be generated.

Find an ACDS-member provider in your area that does patch test on the ACDS website.

We publish articles by doctors who wish to provide helpful information to their patients and the public, or who respond to our requests to use them as professional resources. Doctors may or may not prefer to remain anonymous and we respect this preference. These resource articles do not in any way imply an endorsement by the physician of or VMV HYPOALLERGENICS® — they are intended for informational purposes only. While written by or with resource professionals, these articles should not be relied on for diagnostic accuracy or applicability to your particular skin, which requires an in-person ocular consultation with a qualified physician and possibly additional diagnostic tests.