What can you do to stop itching in the hand if you have a fracture?

Hair dryer. If you're in a cast or splint using a hair dryer on a cool setting to blow cool air in the cast can help. Sometimes an antihistamine like Benadryl (diphenhydramine) might help but it can make you drowsy.
Benadryl (diphenhydramine) cream. I find Benadryl (diphenhydramine) cream or a mild cortisone cream can help with the symptoms of itching. Itching is generally due to inflammation and the new growth of cells, blood vessels, and nerves. So most of these symptoms are a normal response. However, inflammation can lead to infection if the tissue is overwhelmed and cannot fight off the infection through a normal body's response.