If you notice itchiness, redness, or peeling on your lips, one explanation could be contact dermatitis, which, as Dr. Hayag explained, is an allergic reaction that can occur from having contact with certain foods, lip products, jewelry, and even toothpaste. "Allergic triggers can be not only lip products but other makeup, skincare, and toothpaste," she told POPSUGAR. "Cinnamic acid or cinnamon derivatives are common allergens in toothpaste."
According to Dr. Hayag, some common ingredients found in lip products that can cause irritation are vitamin E, castor oil, lanolin, and fragrances or flavorings. "A lot of lip balms contain these ingredients," she said. "Treatment is to find the cause and eliminate it. You don't necessarily develop a reaction right away after using a product. It's common to develop an allergy to an ingredient that you have been using for some time."
The best way to figure out what's causing irritation is by process of elimination, stopping the use of each product you think might be the culprit and then re-adding them to your routine after a few weeks.
"This is challenging and time consuming, so if all fails a visit to a dermatologist for a consultation and patch testing to likely ingredients would be prudent," Dr. Hayag said. "Using a topical steroid cream will help clear up the problem unless you are still using the suspected culprit."