Allergic reactions to personal care products are common: up to 24 percent of Americans experience an allergic skin reaction during their lives, which a doctor will call contact dermatitis. The immune system overreacts to chemicals considered harmless to most people, and hair cleansing products are, in fact, a leading cause of contact dermatitis. Even with regular use without incident, a reaction is still possible. An allergic reaction to shampoo can leave you with an itchy scalp and hair loss.
What might you be allergic to?
Shampoos are typically formulated with up to 30 ingredients including ‘surfactants’ which aid in cleansing and lathering, ‘conditioners,’ ‘active ingredients’ which soften the hair and scalp, ‘additives’ which stabilize the formula and modify its effects – and fragrance. Choosing hair care products with fewer ingredients is one way to reduce the risk – or narrow the possibilities and hone in on the culprit. Establishing a gentle hair care routine can help eliminate chemical irritants and boost hair growth.
According to Medscape.com, fragrance is the most commonly present allergen. The next most common is the cleansing agent cocamidopropyl betaine (CAPB), followed by preservatives with antifungal and antibacterial effects: methylchloroisothiazolinone/methylisothiazolinone (MCI/MI), dimethylol dimethyl [DMDM] hydantoin, diazolidinyl urea, quaternium-15, followed by preservatives imidazolidinylurea, Iodopropynyl butyl carbamate (IPBC), and methyldibromoglutaronitrile/phenoxyethanol (MDBGN/PE).
Your skin will be the first to tell you that it has come in contact with an allergen, and while symptoms usually appear within 48 hours, abnormal skin conditions can take up to a week after exposure to appear.
Additionally, propylene glycol, a chemical solvent and emulsifying agent, the antioxidant vitamin E (tocopherol), and benzophenones, used to absorb UV light, are all potential allergens. These allergens can create shampoo allergy symptoms in people leading to skin irritation and irritant dermatitis.
What are the symptoms of an allergic reaction?
Your skin will be the first to tell you that it has come in contact with an allergen, and while symptoms usually appear within 48 hours, abnormal skin conditions can take up to a week after exposure to appear. People have different allergic reactions to shampoo, but the most common adverse reactions take place in one or more areas of the eyelids, face, neck, scalp, or upper back. Additional symptoms include:
- Red, burning, or itchy skin
- Scaly patches
- Oozing blisters
- Sun sensitivity
What do I do if I have an allergic reaction?
A thorough exam with questions about your symptoms and a physical exam, may provide your doctor with everything they need to diagnose your condition. However, your doctor may suggest you consult an allergist for a patch test to further narrow down your allergy. A patch test involves applying small samples of potential irritants on your back and monitoring any effects such as a rash. Rashes can also slow your hair growth rate, which can be frustrating when you don’t know why your hair isn’t growing.
If you know you are especially chemically sensitive, this is something your colorist will do to gauge the effects of color chemicals on your system. Many permanent and some semi-permanent dyes contain paraphenylenediamine (PPD), which is the most common cause of allergic reactions. Options include temporary color and henna.
Keep track of your symptoms to help with a diagnosis. Take note of these details:
- What were you doing in the days and hours before your outbreak?
- Which products were you using before the reaction occurred?
- How much and how often were you using them?
- Where on your body did you use them?
- What symptoms do or did you have?
- Have you experienced skin reactions before?
- What treatments, if any have you undergone to address previous reactions?
What do I do to avoid an allergic reaction?
Once you know what you’re allergic to, be thorough in your efforts to shun it. If you use shampoos to wash hair daily, decreasing the frequency of use should be your first action.
- After contact, wash thoroughly with hypoallergenic soap and water as soon as possible, and wash your hands before touching any other part of your body.
- Remove and wash clothes or jewelry that the irritant may have touched.
- Treat mild reactions with Aloe Vera, Calamine lotion, antihistamine- or Cortisone-based ointments.
- Prescription medications are available for more severe reactions if needed.
Patch-testing for a shampoo allergy isn’t easy. Sensitive skin tends to have a stronger skin reaction leading to more severe allergy symptoms. Several allergens in shampoo have not yet been included in current lists of suspects and may result in testing with the shampoo itself rather than its individual ingredients.
Similar ingredients are used in various brands, and simply switching to another shampoo may not be sufficient. You could complicate your diagnosis by introducing too many variables.
Approximately 1 to 4% of the general population will have positive patch-test reactions to fragrances, though the short time the body is exposed to them in shampoo makes them less risky than fragrances in leave-on products. If you know that your skin is especially sensitive historically, avoid synthetic fragrance, or search for fragrance-free products.
To make your allergen detective work even more challenging, fragrances are considered trade secrets, and their specific ingredients are not required to be listed in the US, although the EU differs in this practice and requires a complete list. Avoiding a specific chemical then can be impossible if you don’t know it’s there. To be completely risk-free, choose products that are labeled fragrance-free.
Shampoos contain a wide variety of potential allergens, and for people with sensitive skin or who are allergic to multiple ingredients in a formula, finding a hypoallergenic shampoo isn’t easy. However, there is hope in a product called New Wash, a cleanser that is about as different from shampoo as one can get.
First off, it contains no detergent whatsoever, which eliminates potential allergies to surfactants. Second, the preservative system used is completely natural. Third, the fragrance is composed primarily of essential oils and extracts. Every single ingredient is listed – and since the recipe is what makes our rosy-fresh aroma so beloved, this trade secret is quite safe. Your skin will be too.