Hair Product Allergies

Hair care products are a pretty common item found in the modern woman’s (and man’s) life. There are products that cleanse, condition, smooth, style, protect, and thicken the hair. These products go through rigorous testing to ensure their safety for use by people of the recommended ages and, generally speaking, they are helpful and rarely harmful.
However, some people find that they have an intolerance for some products that others have no difficulties using. This intolerance typically takes the form of an allergic reaction, the severity of which may vary.
In order to discuss these types of reactions, we should briefly discuss the nature of allergic reactions in general to help us create a baseline of understanding of the terms and concepts involved.
Allergy Basics:
An allergy is simply defined as "a harmful immune response to an antigen that is not in and of itself harmful". This means that the substance that triggers an allergy may not be specifically harmful, but that the body with which it comes into contact has an immune response to the substance which is harmful. There are four mechanisms found in allergic reactions. These are:
• Immediate Hypersensitivities
• Antibody-Mediated Cytotoxicity
• Immune Complex Disorders
• Cell-Mediated Hypersensitivities
Of these mechanisms, the first and fourth (Immediate and Cell-Mediated Hypersensitivities) are the ones most likely to occur in connection with using hair care products (or any other food or product). The second (antibody-mediated cytotoxicity) and third (immune complex disorders) usually relate to longer-term and innate health conditions, such as Rh disease in newborn babies, Myasthenia Gravis, Lupus, and varied Serum sicknesses and disorders.
The hypersensitivities are those that are generally reactions to the antigens that are either ingested (inhaled, swallowed) or contacted through the skin and absorbed in that way. These can produce histamine reactions (such as hay fever and asthma) or dermatitis such as the rashes of hives and poison ivy.
What this Means:
Now, we could get bogged down in the details and biology of allergic mechanisms and responses, but to keep things simple, this means that with any hair care product (since that is what we are mainly concerned with here) some individuals may have a sensitivity to an ingredient within the product that creates a harmful result.
Woman with an itchy scalp and hair
Photo: Gpoint Studio/Canva
These responses are specific to an individual and depend on that individual’s specific sensitivities and the specific biochemistry of the individual. In other words, one woman may try a product and have no issue with it whatsoever, while her friend may try the same product and develop a rash. Even if two people are sensitive to a product, one person may have a histamine reaction to the fragrance of the product, causing them to have an asthma attack, while the other develops a painful rash after applying the same product.
The level of sensitivity (in fact, the presence of sensitivity) can depend on factors like other substances and interactions, hormone levels, diminished immunities, or underlying illnesses. Women, especially, can be subject to changes in their sensitivity to products because of their bodies' constantly changing hormonal balance.
Girls in puberty, women going through menopause, women having their period, and women who are pregnant may all experience reactions to products they have used before, or may find that - during certain times in their lives – products which they previously couldn't tolerate no longer affect them.
It is also a fact that sometimes you can develop sensitivity to a substance as a result of prolonged or repeated exposure to it. So, the hair gel that you had been using for years could be the cause of the mysterious itch and redness on your scalp simply because your body has developed sensitivity to it.
How to Use This Information:
At first glance, one would think that using a hair care product (or anything in our world) is a gamble, and in some ways it is. But rather than be alarmist, think of this as a way to understand how to deal with the things that may come up when you are dealing with your hair care products. If you start experiencing irritation or unusual symptoms after beginning to use a new product, obviously discontinue using it.
However, if the symptoms occur and you can't identify the cause easily, then try eliminating all the products until the symptoms subside, and add them back in one at a time so that you can identify the cause/trigger. And as always, if you have severe reactions/symptoms, see a medical professional for help.
NOTE: This information is meant to share education and basic knowledge of some of the conditions associated with allergic reactions to hair care products. This is not intended to be medical advice or a substitute for medical professional evaluation of any medical condition. As always, see your doctor when you have any skin irritation or allergic reaction.
See also:
Hair color allergies
Choosing a hair product
How to do a patch test