Swelling after applying medicine to a finger scratch may be caused by improper medication, bacterial infection, subcutaneous hematoma, tissue edema and other reasons. 1. Improper use of medication: such as the application of drugs can not control bacterial infection, the dose of medication is not enough, the adverse reaction of the drug, etc., may lead to the phenomenon of finger cuts swollen after applying medication. If the wound does not follow the doctor’s advice, topical use of creams that do not contain antibiotics, or creams that will cause the injured person’s own allergies, etc., swelling may occur. 2. Bacterial infection: wounds usually lead to bacterial infection, causing local inflammatory reaction, improper treatment, swelling will occur. 3. Subcutaneous hematoma: If the subcutaneous blood vessels are damaged, it can cause hematoma under the skin, and swelling may occur after applying medication. 4. Tissue edema: Tissue edema may occur after the skin is traumatized, and cannot be relieved immediately after applying the medicine. It is recommended that people with finger cuts go to the hospital in time to clarify the cause, and if treatment is needed, it should be standardized under the guidance of a doctor, and should not be blindly self-medication, so as not to delay the condition.