Sometimes being a hairstylist can feel more like being a hair doctor. You want to help your clients maintain the healthiest hair possible. By now it’s common knowledge that not all shampoo is good for the health of your hair. But some shampoos and other products may also be irritating to the scalp and cause allergic reactions, especially if you have sensitive skin. The scalp is skin too, after all!

According to Dr. Gaby Longsworth, certified hair practitioner and Ph.D. scientist at AbsolutelyEverythingCurly.com, "The top three sources for scalp-only allergens are hair dyes, shampoo/conditioners, and consumer items."

Scalp itchiness and flakiness may be something your clients try to ignore, but they don’t have to endure it. By advising them to use high-quality, non-irritating haircare products, you can help them reclaim comfort on top of their dome, which will also do great things for the health and growth of their hair. Start by checking their symptoms:

Symptoms Indicative of a Scalp Allergy

• Scalp sensitivity

• Persistent itch

• Rashes on the scalp 

• Little bumps on the scalp, forehead, neck, and behind the ears

• Scaly skin 

• Flaking skin

• Their anti-dandruff treatment not working (because it is an allergy)

If your client is experiencing any of these bothersome symptoms, it’s possible that they may have a scalp allergy. Dr. Longsworth recommends that they check the ingredient list of any products they use on thier hair:

12 Ingredients That Can Cause an Allergic Reaction

Listed in order of most to least common:

1. Fragrances – It is difficult to identify the fragrances that may cause issues because companies keep these a trade secret. If you suspect you are having an allergic reaction, try using fragrance-free products until you figure out the culprit.

2. Hair bleach – The treatment itself can be irritating to the scalp but the irritation usually subsides within a few days.

3. Isothiazolinones (preservatives), including:

   • Methylchloroisothiazolinone (MCI), also known as an itchy M 

   • Methylisothiazolinone (MI), the other itchy M

   • 5-chloro-2-methyl-4-isothiazolin-3-one

   • Kathon

   • 5-chloro-2-methyl-2H-isothiazol-3-one

   • 2-methyl-2H-isothiazol-3-one

   • 2-methyl-4-isothiazolin-3-one

   • 2-methyl-3(2H)-isothiazol-3-one

4. Formaldehyde-releasing preservatives, including:

   • dimethylol dimethyl (DMDM) hydantoin

   • diazolidinyl urea

   • quaternium-15 (positive reaction in about 9% of users)

   • imidazolidinylurea

   • Parabens 

5. Propylene glycol, a water-soluble emulsifying agent

6. Vitamin E (tocopherol) 

7. Benzophenones – ultraviolet light absorbers that protect against UV light

8. Iodopropynyl butyl carbamate (IPBC) – a non-formaldehyde preservative

9. Methyldibromoglutaronitrile & phenoxyethanol in combination is a significant source of allergic dermatitis

10. P-phenylenediamine – common in hair dyes

11. Balsam of Peru – a common cause of allergic contact dermatitis; it smells like vanilla and cinnamon

12. Cinnamic aldehyde – the compound that gives cinnamon its flavor and odor; often found in fragrances

As a side note, these ingredients will not be irritating to everyone. If you or your client happen to find these ingredients in your products but don’t suspect they’re causing an allergy, it’s not necessary to swear it off. However, if your client is having scalp issues, recommend that they try replacing any products with these ingredients to see if their scalp shows improvement. Hopefully they’ll end up with a healthy, irritation-free scalp, the best environment for hair growth.

If your client needs recommendations on what products to use instead, Dr. Longsworth recommends the Shea Radiance haircare line.

Sensitive Scalp Product Recommendations

• Maximum Moisture Shampoo ($14) This moisturizing shampoo for all hair textures will cleanse your hair without stripping its natural oils. Key ingredients like shea butter, castor oil, and hemp seed oil will leave your hair soft, nourished, and manageable with gentle foam. P.S. it's color-safe, paraben-free, and contains no dyes, synthetic fragrance or SLS.

• Maximum Moisture Conditioner ($16) A nourishing shea butter conditioner for all hair textures, especially for dry, brittle hair that leaves hair feeling soft and fluffy. Key ingredients like rice protein and keratin help to strengthen the hair shaft and prevent breakage. P.S. it's color-safe, paraben-free, and contains no dyes, synthetic fragrance or SLS.

• Keratin Deep Conditioning Mask ($20) A deep conditioning hair mask for all textures infused with proteins that penetrate deep into your hair’s cortex to fortify, protect, and support hair growth. P.S. it's color-safe, paraben-free, and contains no dyes, synthetic fragrance or SLS.