A cast protects a broken bone or other injury while it heals. Most casts are made of fiberglass. After a cast is put on, you can't remove it yourself. Your doctor or a technician will take it off.
- Follow your doctor's instructions for when you can start using the limb that has the cast. Fiberglass casts dry quickly and are soon hard enough to protect the injured arm or leg.
- When it's okay to put weight on your leg or foot cast, don't stand or walk on it unless it's designed for walking.
- Prop up the injured arm or leg on a pillow anytime you sit or lie down during the first 3 days. Try to keep it above the level of your heart. This will help reduce swelling.
- Put ice or a cold pack on your cast for 10 to 20 minutes at a time. Try to do this every 1 to 2 hours for the next 3 days (when you are awake). Put a thin cloth between the ice and your cast. Keep the cast dry.
- Be safe with medicines. Read and follow all instructions on the label.
- If the doctor gave you a prescription medicine for pain, take it as prescribed.
- If you are not taking a prescription pain medicine, ask your doctor if you can take an over-the-counter medicine.
- Do exercises as instructed by your doctor or physical therapist. These exercises will help keep your muscles strong and your joints flexible while you heal.
- Wiggle your fingers or toes on the injured arm or leg often. This helps reduce swelling and stiffness.
Water and your cast
- Try to keep your cast as dry as you can. The fiberglass part of your cast can get wet. But getting the inside wet can cause problems.
- Use a bag or tape a sheet of plastic to cover your cast when you take a shower or bath or when you have any other contact with water. (Don't take a bath unless you can keep the cast out of the water.) Moisture can collect under the cast and cause skin irritation and itching. It can make infection more likely if you have had surgery or have a wound under the cast.
- If you have a water-resistant cast, ask your doctor how often it can get wet and how to take care of it.
Cast and skin care
- Try blowing cool air from a hair dryer or fan into the cast to help relieve itching. Never stick items under your cast to scratch the skin.
- Don't use oils or lotions near your cast. If the skin gets red or irritated around the edge of the cast, you may pad the edges with a soft material or use tape to cover them.
When to call for help
Call your doctor now or seek immediate medical care if:
- You have increased or severe pain.
- You feel a warm or painful spot under the cast.
- You have problems with your cast. For example:
- The skin under the cast burns or stings.
- The cast feels too tight or too loose.
- There is a lot of swelling near the cast. (Some swelling is normal.)
- You have a new fever.
- There is drainage or a bad smell coming from the cast.
- Your foot or hand is cool or pale or changes color.
- You have trouble moving your fingers or toes.
- You have symptoms of a blood clot in your arm or leg (called a deep vein thrombosis). These may include:
- Pain in the arm, calf, back of the knee, thigh, or groin.
- Redness and swelling in the arm, leg, or groin.
Watch closely for changes in your health, and be sure to contact your doctor if:
- The cast is breaking apart.
- You are not getting better as expected.
Current as of: July 1, 2021
Author: Healthwise Staff
Adam Husney MD - Family Medicine
Kathleen Romito MD - Family Medicine
Martin J. Gabica MD - Family Medicine