Am Fam Physician. 2002;66(8):1524
Why do I need a cast?
A cast can help keep the injured area from moving so you can heal faster without risking further injury. How long you'll need to wear a cast depends on the type of injury you have and how serious it is. Your doctor may want to check your cast 1 to 3 days after putting it on to be sure that it isn't too tight and that your injury is starting to heal.
If I have a broken bone, will it continue to hurt?
Almost all broken bones cause pain. The cast should relieve some pain by limiting your movements. Your pain should become less severe each day. Call your doctor immediately if the pain in the casted area gets worse after the cast has been applied. You should also call your doctor right away if you have new pain that develops in another area (for example, pain in your fingers or forearm if you have a wrist or thumb injury, or pain in your toes or calf if you have an ankle or foot injury).
New pain may mean that the cast is too tight. If you have this symptom, raise your cast. This may reduce pain and swelling. Your doctor will probably want to see you right away to check the cast.
Is it okay to get the cast wet?
With some fiberglass casts, you can swim and bathe. However, most casts shouldn't get wet. If you get one of these casts wet, irritation and infection of the skin could develop. Talk to your doctor about how to care for your cast.
To avoid getting the cast wet during bathing, you can put a plastic bag over the cast and hold it with a rubber band. If the cast does get wet, you may be able to dry out the inside padding with a blow-dryer. (Use a low [cool] setting, and blow the air through the outside of the cast.) Ask your doctor before trying this.
What can I do about itching?
If your skin itches underneath the cast, don't slip anything inside the cast, because it may damage your skin, and you could get an infection. Try tapping the cast or blowing cool air from a blow-dryer down into the cast.