Why Is My Cast So Itchy and How to Stop It?

Closeup of Asian man's arm with long arm plaster, fiberglass cast therapy cover by blue elastic bandage after sport injury.
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When you have a broken bone, the last thing you want is an itchy cast. Unfortunately, being itchy in a cast is a common problem. And for some, the itchiness can be unbearable. 

Although the cast protects the injured limb, it can also trap itch-inducing bacteria underneath the surface. Luckily, there are a few things you can do to ease the itch. In this blog post, we'll discuss some of the best ways to relieve your itchy skin while wearing a cast!

Why Does It Itch When You Have a Cast? 

Itching under a cast is a common, yet frustrating, experience for many people. It can be caused by a number of things, including dry skin, contact dermatitis, and even nerve damage. 

Let’s dive deeper into the reasons you have an itchy cast:

  • Nerves: when the cast hardens and starts to dry, the nerve endings in the skin can fire, sending signals to the brain that cause itching.
  • Trapped moisture: damp conditions under the cast provide the perfect environment for bacteria to thrive and multiply, which can cause skin irritation.
  • Immune response: histamines may be released by the body in response to the plaster or fiberglass being recognized as foreign invaders. Released histamine can cause itching, redness, and swelling. 
  • Dead skin cells: as new skin cells are generated and old skin cells shed, they can get trapped against the cast and cause itching.
  • Body hair: the layers of cotton wrapping can pull body hair and make the skin itchy and irritated.

What to Do When Your Cast Itches 

Woman with itchy arm cast consulting her doctor
Elnur - stock.adobe

While wearing a cast, there are several things you can do to relieve the discomfort and make it more comfortable. With a little trial and error, you should be able to find something that helps relieve your itchy skin! Let's take a look at the best options for scratching your itch while wearing a cast. 

Barrier Cream Before Applying Cast

If you have sensitive skin, the cast can cause irritation, itchiness, and even pain. Fortunately, there are ways to help reduce these problems. Before getting your cast put on, ask your doctor about applying a barrier cream or lotion to your skin. This can help to create a barrier between your skin and the cast, preventing the materials from coming into direct contact with your skin.

Don’t Shove (Sharp) Objects Down the Cast 

It can be incredibly tempting to scratch an itch by shoving objects down your cast. Unfortunately, this can lead to a number of problems. First, scratching with a butter knife, pencil, thin tool, or other objects can break the skin and can lead to infection. Second, as casts are typically worn for weeks at a time, you may not realize you have an infection until your cast comes off. By then, you may be feeling seriously unwell.

Instead, try using a soft cloth or thin towel to lightly rub around the cast. You can also try gently scratching the itch with a cotton swab. This can help to stimulate blood flow and provide relief. 

Keep the Cast Dry 

Patient drying their fiberglass arm cast with a hair dryer
Филипп Очеретный - stock.adobe

One of the most important things to remember when you have a cast is to keep it dry. When your cast gets wet, the plaster expands and rubs against your skin, which can aggravate the itch. In addition, you risk damaging the cast and delaying the healing process.

There are various types of cast covers that can protect your cast while you shower or swim. For example, there are one-time-use disposable covers and reusable covers made from materials like silicone. If you plan on spending time in the water, look for a cast cover that is waterproof and has an airtight seal. 

If you must get your cast wet without a cast cover, consult with your doctor, and be sure to dry the cast thoroughly afterward with a hair dryer on the cool setting. 

Keep the Cast Clean 

When you have a cast, it's important to keep the area clean to avoid itchiness and irritation. Dirt and sand can make the itching worse, so it's best to stay away from them if possible. If you have a waterproof cast, rinsing the area with water after sweating or swimming can prevent sores and itchiness. Just be sure to allow the water to drain afterward so that the area can dry completely. 

Blow Cool Air in the Cast 

Blowing cool air into the plaster or fiberglass cast allows airflow to circulate, helping to dry out the skin and preventing bacteria from growing, which can contribute to itchiness. To use a hair dryer on your cast, blow air on the itchy spot, and move the dryer back and forth until the itch subsides. Another option is to place the casted limb in front of a fan. The moving air will help to cool and dry the skin, which can provide relief from an itch and help to soothe irritated skin.

Cast Anti-itch Spray 

If the itch is particularly bad, you can try using a cast anti-itch spray. This powerful spray provides fast relief from itchiness and can be used on a variety of skin conditions. Simply apply the spray to the affected area and enjoy immediate relief. In addition, the spray helps to soothe and protect the skin, and can even be used as a preventative measure against future itchiness. Be sure to ask your doctor before using any new products, as some may not be compatible with your cast material.

Ice Packs or Cold Compress 

If all else fails, you can always try the old standby of using a cold compress or ice pack. These can help to numb the itch and provide some temporary relief.

Antihistamine for Itchy Cast

If you're still struggling with an itch, you may want to consider taking an antihistamine like Benadryl. Antihistamines work by blocking the release of histamine, which is a chemical that plays a role in the body's immune response. When histamines are released, they cause itching, swelling, and other allergic symptoms. By blocking the release of histamines, antihistamines can help to relieve the itchiness associated with a cast. Antihistamines are available over-the-counter, so they're easily accessible. And, they're typically safe and well-tolerated. However, always check with your doctor first to make sure it's safe for you to take. 

Consult your Doctor 

Don't forget that you can always call your doctor if the itching is severe or if you notice any skin irritation, foul odor, or discharge from your cast. They may be able to provide additional itch relief strategies, cast care tips, or even suggest you get a new cast.

In addition, if you suddenly lose the ability to move your fingers and toes, it is important to see your physician right away. Numbness in your extremities can be a sign of nerve damage. 

Consider Switching to Cast21 

What if you could switch to a cast that didn't make you itch in the first place? That's where Cast21 comes in. We make itch-free cast alternatives that are just as strong and durable as traditional plaster or fiberglass casts. Plus, our unique design means that your Cast21 product will actually be more comfortable to wear. So if you're tired of dealing with an itchy cast, ask your doctor if you can make the switch to Cast21. You'll be glad you did. 

If you have any questions about Cast21 or would like to learn more about our products and services, please don't hesitate to contact us. We would be more than happy to answer any of your questions and help you get on the road to recovery. 

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