The exact reason why scabs itch isn't completely clear, but scientists have a few theories. When you get a cut or scrape, your body releases chemicals called histamines, which may cause irritation and itching. And as the wound heals, the action of new cell formation can be interpreted by the brain as an itching sensation.
An itchy scab can be irritating, but it’s typically a sign that a wound is healing correctly.
1. How Wounds Heal
When you injure yourself and cut, scrape, or burn your skin, blood begins to clot in order to stop the blood from excessively leaving your body. Blood clotting happens thanks to cells called platelets. Forming platelets is the body’s way to patch up a leak.
Eventually, when the wound stops bleeding, a scab forms. The scab helps protect the freshly injured skin from contaminants like bacteria and allows the skin to heal.
Underneath a scab, your body is working hard to repair damage to the skin and blood vessels. The body also enlists white blood cells to help clean up any foreign matter and bacteria in the wound. After some time, a scab will fall off to reveal brand-new skin. It’s a pretty amazing process.
Of course, the body can’t repair all wounds this way. Deep wounds and severe burns require emergency medical treatment. But most small nicks, cuts, scrapes, and surface burns heal well on their own in a healthy person.
2. Why Scabs Itch
Itching occurs as a normal part of healing. However, the reason the itch develops isn't completely understood.2
One study from 2016 suggests that the same mechanisms at work with eczema itchiness are involved in itching during wound healing.3
Additionally, itching that occurs during wound healing might be the result of poorly translated nerve signals. The nerves under your skin transmit information to your brain, but they’re not always good at passing along the message in a comprehensive way.
Your brain might receive a signal that your skin is regenerating via collagen synthesis, but that information is translated as an itching sensation. And so, what you feel is that itching sensation.
While some experts believe histamines, which are released by the body to help with wound healing, may contribute to itching, research suggests that their effect may be minimal.
3. Why You Shouldn’t Scratch
Scratching an itch feels great. It’s so satisfying, in fact, that people tend to scratch even when they really shouldn’t. Scratching an itchy wound that is in the process of healing, however, can cause scarring and prolong healing if you open the wound back up again.
You might even introduce bacteria, causing an infection to develop.
4. How to Stop Itching
Itching can sometimes be excruciating, even more so if you’re trying not to scratch. However, it’s important to avoid excessive scratching because it can cause the wound to open up again. By alleviating the itch, you can avoid a prolonged healing process and potential infection from scratching too much. Here are a few ways to stop the itching:
Applying cold or warm compresses
Moisturizing
Avoiding tight clothing or accessories worn around the wound
Covering the wound with a bandage
Applying over-the-counter (OTC) anti-itch creams
Bathing in lukewarm water with added moisturizers or oatmeal
It may also help to find effective distractions from the itching. If itching is very severe and there is a high risk of infection, your healthcare provider may recommend a sleep medication or a neuropathic drug called Neurontin (gabapentin) to help you rest and decrease the urge to itch.