A hard bag on the back of the hand can be caused by tendon sheath cysts, common warts, urticaria, etc. It can be improved by medication and physical therapy. 1. tendon sheath cysts: hand joint capsule, ligament, tendon sheath in the connective tissue and other degenerative changes will lead to the occurrence of tendon sheath cysts in the hand, so that the back of the hand and other parts of the hard bag, swelling and other symptoms, such patients can be injected through the tendon sheath cysts in the area of the hormone drugs (such as tricholoma acetate, prednisone acetate and so on) to help improve the relevant symptoms. 2. common warts: the back of the hand infected with human papillomavirus will lead to local common warts, thus showing the back of the hand rough, hard mass-like organisms and other symptoms, this kind of patients can use the laser, freezing, electrocautery and other physical methods to help remove the back of the hand common warts, usually has a better effect. 3. urticaria: some urticaria patients due to the back of the hand skin, mucous membrane small blood vessels dilation and exudation increase, will also lead to the back of the hand hard bags, air masses and other symptoms, and more accompanied by varying degrees of itching symptoms, such patients can be applied through the local glycerine lotion, benadryl cream and other drugs to help stop the itch, the serious need to oral cetirizine and other medications for antiallergic treatment. A hard bag on the back of the hand may also be caused by other reasons, it is recommended to consult a doctor in a timely manner, to clarify the cause of the disease in the doctor’s guidance, to avoid the occurrence of adverse reactions.