How To Care For Your Child's Non-Waterproof Cast

Standard Cast Care Tips and Management

Doctors use fiberglass or plaster wrap (or sometimes both) to make your child's cast.

It will harden before you leave the Emergency Department (ED) or the orthopaedic office. Please note: the ED at UPMC Children's Hospital of Pittsburgh does not do waterproof casting.

Your child's cast may take up to 2 days to dry all the way.

The cast helps keep your child's injured arm or leg properly aligned and protects the bone while it heals.

While a cast will help with pain related to the injury, it won't take it away completely.

The doctors in the ED may give your child medicine to help with pain. Acetaminophen (Tylenol), ibuprofen (Motrin, Advil), and other anti-inflammatory drugs are usually the most effective.

You will not be able to remove the cast yourself. Attempting to do so may cause serious injury.

Basic Tips on How To Care For Your Child's Cast

The doctor will go over cast care details with you.

But based on questions parents most often ask, here are a few tips:

  • Weight. Follow what the doctor says about when your child can first put weight on the cast.
  • Elevation. For the first 3 days, prop your child's casted limb on a chair or pillow when sitting or lying down. Make sure it's above the level of their heart. This will help decrease swelling.
  • Movement. Have your child wiggle their fingers or toes in the casted arm or leg once an hour during the day. This improves blood flow to the injured limb. It's normal for the color of these fingers or toes to differ slightly from the uninjured site.
  • Pain management. You can give your child Tylenol or ibuprofen as needed for pain.

How to tell if your child's cast is too tight

Broken bones can swell, which can create pressure under a child's cast. The doctor may split the cast if there's concern about swelling.

Casts may feel as if they're too tight immediately after the doctor applies it. Please elevate the limb and wait for a few hours to observe if the fingers or toes swell.

A cast that's too tight may cause:

  • Swelling of the fingers or toes of the casted area.
  • Sensations such as numbness or tingling under the cast. These sensations are common but should not worsen over time. If they do, contact your doctor.
  • Loss of ability to move fingers or toes of the casted arm or foot.

These are all reasons to call the doctor. See below for other reasons to call your doctor.

How to shower with a non-waterproof cast

Standard casts are not waterproof. This means you need to keep it clean and dry. Never put the cast under water.

When your child showers:

  • Place a towel around the arm or leg above the cast. Then wrap plastic bags (or trash bags) over the cast and seal with an elastic band or tape around the towel.
  • Only sponge bathe areas closest to the cast.
  • Remove the bag right after the shower. If the edges of the cast get slightly wet, don't cover them until they dry. Use a hair dryer on a cool or very low heat setting to help dry the cast.

Commercial cast covers can help with splatter from a shower. But, they won't keep casts dry in a bathtub or swimming pool, despite what the manufacturer may claim. Call your doctor if the cast gets dripping wet or soaked.

If your child did receive a waterproof cast, learn more about waterproof cast care.

Skin care

Doctors often cover the edges of the cast with a soft fabric wrap. Sometimes this fabric gets worn or torn.

You can add moleskin to keep the cast edges smooth. You can find it at most drug stores and online.

Check the skin around the cast once in the morning and once at night.

Make sure to:

  • Look under the edges of the cast.
  • Notice if skin is red, irritated, swollen, or broken.

Itchy skin

The skin under the cast can get itchy. Never put anything down into the cast to scratch.


  • Use a hair dryer on a cool, low setting and blow air into the cast.
  • Use your knuckles to knock on the cast around the itchy area.
  • Give your child diphenhydramine (Benadryl) for severe itching.

When To Call the Doctor

Seek health care right away if your child has:

  • Numbness or tingling that doesn't go away with a change of position.
  • Severe pain when moving fingers or toes of the casted arm or leg.
  • Extreme soreness, redness, or blueness of fingers or toes.
  • Coolness of the casted arm or leg that doesn't go away.
  • A bad smell or drainage from the cast.
  • A decreased ability to move fingers or toes.
  • Severe itching that doesn't go away.
  • Red, broken, or swollen skin around or under the cast.
  • Cracks, splints, or softening of the cast.
  • A fever above 101°F (38.5°C) by mouth lasting more than one day.

Scheduled Cast Care Follow-up

  • Follow up in 5 to 7 days at the Orthopaedics Clinic at UPMC Children's Hospital. Our number is 412-692-5530. Or you can follow up with your child's own orthopaedic doctor.
  • Call our clinic on the next business day between 9 a.m. and 5 p.m. to schedule your child's follow-up visit. We don't see people without an appointment.
  • After 5 p.m. on weekdays or on weekends and holidays, call 412-692-5325. Ask to speak with the orthopaedics resident on-call for any urgent questions.