A person should see a doctor for treatment of an allergy to hair dye if signs such as swelling, burning, itching or redness are observed after using the dye, according to Health.com. Although a severe allergy is not common, hives and blisters may develop and difficulty breathing may occur, such as the reaction seen in anaphylactic shock. Treatment may involve pills such as antihistamines or topical creams.
Only one in every 250,000 people is allergic to hair dye, according to Health.com. However, the allergy can be as serious as allergies to shellfish or nuts. The reaction may not be observed with the first or second use of the dye, so it is important to be diligent with every application to note signs of allergic reaction.
Although allergies to hair dye are rare, people should perform a skin patch test prior to use and wait 48 hours to determine whether an allergy is present. A patch test involves applying a tiny amount of dye on the skin and observing the skin for signs of allergy.
Those people who are allergic to hair dye should consider using dyes that are made with natural ingredients, such as henna, to reduce the risk of allergic reactions during the coloring process.