A hard lump after anesthesia injection, which is not painful or itchy, may be caused by malabsorption, allergy, improper care and so on. 1. Poor absorption: the medicine is not well absorbed after anesthesia injection, which will lead to the anesthetic collecting under the skin, thus leading to a hard lump after anesthesia injection without pain or itching. 2. Allergy: if you belong to the allergic body, have an allergic reaction to anesthesia medicine, and cause allergy after anesthesia medicine, it may lead to a hard lump in the local area which is not painful and itchy. 3. Improper care: after anesthesia injection site will be left with a needle eye, avoid water within 24 hours, but also pay attention to local cleanliness and hygiene, if improper care leads to infection of the injection site, there may be a hard lump in the early stage of the pain does not itch. After anesthesia injection, there is a hard lump, no pain, no itch, it is recommended to go to the hospital, clear the cause of the disease to comply with the doctor’s instructions.