The Christmas tree rash is a skin irritation that commonly occurs during the holiday season. It is caused by contact with the sap of a Christmas tree, which contains an allergen that can cause an allergic reaction in some people. Symptoms of the Christmas tree rash include redness, itching, and bumps or blisters on the skin. The rash can be treated with over-the-counter antihistamines, anti-inflammatory creams, and cold compresses. To prevent the Christmas tree rash, it is best to avoid direct contact with the tree sap by wearing gloves when handling the tree.