Flea bites can usually heal on their own, but the time it takes for them to heal varies from person to person and may be a few hours or a few days. If you are accidentally bitten by a flea, you will get a bag on your body, which may be accompanied by itchy skin. Usually, people with mild symptoms can heal themselves in a few hours. If you are allergic, after being bitten by a flea, not only will you get a bag on your body, but the itching of your skin will also be more serious, and it may take a few days to heal itself, such as about 3-5 days, or more than 5 days. After being bitten by fleas, for the symptoms of skin bags and itching, it is best not to scratch with your hands, you can apply some anti-inflammatory and anti-itching ointment as prescribed by the doctor, such as mometasone furoate cream, fludioxonil acetate ointment and so on. If the flea bites the bag, caused by allergic symptoms, skin itching is more serious, it is recommended to go to the regular hospital in a timely manner, by a professional doctor for symptomatic treatment.