Many commercial shampoos contain a lot of chemicals, scents and other potential irritants. These elements may make the product smell good and can lead to silky hair, but they also can cause allergic reactions in some people. Signs of an allergic reaction to shampoo include itching, blotchy skin, flaky scalp and swelling. It is important for people to remember that an allergic reaction does not always show signs immediately after a shower. Symptoms can sometimes take more than 24 hours to begin.
One sign of an allergic reaction to hair products is excessive itching that may be accompanied by red blotches or a rash. The itching may be limited to a person's scalp, but it also can involve areas the shampoo touched as it ran down the body during a shower, including the back, breasts, arms, stomach and even genitals. If the person also gets hives, he or she should take an over-the-counter antihistamine. Calamine lotion can be used to soothe the skin and help prevent scratching.
A flaky or peeling scalp is another common sign of an allergic reaction. A person who believes his or her flaky scalp is a result of using a specific shampoo should stop using the product immediately. He or she also may find relief by skipping washing his or her hair for a few days and using cool water instead of hot during showers. If the peeling does not seem to be clearing up on its own, the individual should contact his or her medical provider for a prescription treatment. When a flaking scalp is the only symptom present, the healthcare professional also can confirm that it is the result of an allergic reaction to shampoo and is not being caused by an underlying medical condition.
An allergic reaction can also cause swelling. An individual can use cool compresses or over-the-counter antihistamines to reduce minor cases, but when severe swelling is present or if the inflammation is causing the person's throat to close, he or she should go immediately to the emergency room for professional medical treatment.
A person who has had an allergic reaction to shampoo in the past should use preventive measures to avoid future problems. Hypoallergenic shampoos are available to cater to the needs of people with allergies or sensitive skin. Purchasing baby shampoo is another option for people with allergy sensitivities, because products made for infants typically contain fewer irritants. If no over-the-counter shampoo seems to do the trick, a person should turn to a medical professional for a prescription solution.