In some cases, a more severe reaction like anaphylaxis or hives may occur.
Common allergens in shampoos include fragrance chemicals, coconut derivatives, and preservatives such asmethylisothiazolinoneandformaldehyde.
To treat an allergic reaction to shampoo, rinse the area with water and stop using the product.

Image Source / Getty Images
Apply mildhydrocortisone creamor take an antihistamine to reduce symptoms.
Image Source / Getty Images
Can You Be Allergic to Shampoo?
Yes, you might be allergic to shampoo.
This sets off a chain reaction.
These antibodies bind to allergens and to immune cells that then release substances that produce the allergic reaction.
Contact dermatitis may take 24 to 48 hours to develop due to a delayed immune response.
Common Shampoo Allergens
The most common shampoo allergens are fragrance chemicals.
Common fragrance allergens include linalool, limonene, eugenol, and cinnamal.
Do not attempt to treat anaphylaxis with at-home treatments.
It may take up to 10 days for the rash to resolve.
Common shampoo allergens include fragrances, preservatives like formaldehyde, acrylates, and sulfates.
Make an appointment with your healthcare provider or allergist to determine the allergen causing the discomfort.
Alajaji A.Hair product allergy: A review of epidemiology and management.Cureus.
2024 Apr;16(4):e58054.
doi:10.7759/cureus.58054
Groot A.Fragrances: Contact allergy and other adverse effects.Dermatitis.
2015 Dec;90(6):912914. doi:10.1590/abd1806-4841.20153992
American Cancer Society.Formaldehyde and cancer risk.
2021 Apr;32(2).
doi:10.1097/DER.0000000000000668
Mount Sinai.Contact dermatitis.
Nemours Kids Health.Serious allergic reactions (anaphylaxis).
Yale Medicine.Allergic contact dermatitis.