The most benign disadvantage of sunscreen is that it can stain clothes. The most serious side effect can be a severe allergic reaction. Seek help immediately if you experience symptoms like throat swelling and difficulty breathing. Most people won’t experience worse than a rash or skin irritation. You can often solve this issue by trying a different sunscreen. Unless your doctor states otherwise, you shouldn’t skip sunscreen. Many doctors will judge the pros of sunscreen greater than its everyday cons.