Hi & Welcome. I can understand your concern. Allantoin is a natural compound obtained from the plant comfrey & known for its moisturizing, softening, and regenerating abilities. It is also obtained from the urine of most of the animals. Basically used as a skin proctent to treat burns & cuts to soothe and protect the area. It can also be used in the treatment of acne. Common side effects include burning sensation, itching, stinging, redness, or irritation. It may also cause an allergic reaction resulting in skin rash itching, swelling of the face, tongue or throat. Hope this answers your query.