What are scabs?
Scabs are a common symptom of skin infections, immune system skin disorders, and injury. Scabs result from the healing process, in which new skin grows over damaged skin. They may occur in conditions affecting one area of skin alone, or along with more generalized conditions, such as shingles, chickenpox, or eczema. Only in rare situations are scabs found on a significantly large area on the skin.
Wounds due to viral skin infections, including cold sores (herpes simplex), chickenpox (varicella zoster), or shingles (herpes zoster) are common causes of scabs. Blisters, lacerations, abrasions or burns may also cause scabs as they heal. Impetigo, a bacterial skin infection, can also result in scabs. Depending on the cause, scabs may occur only immediately following an acute injury, or they may be due to recurrent breakouts from a chronic condition, such as psoriasis.
A rare autoimmune disorder known as pemphigus vulgaris creates skin blisters and causes scabs, and it may be accompanied by blisters that may appear on the entire body including the scalp and the inside of the mouth. Dermatitis artefacta (self-inflicted sores) and other mental disorders associated with self-mutilation behaviors may cause scabs, including repeated picking, rubbing or scratching.
Rarely are scabs a serious condition. However, any open wound can develop into a serious bacterial infection. Seek prompt medical care (call 911) if you experience scabs along with difficulty breathing, high fever (higher than 101 degrees Fahrenheit), or pus and redness around the scab.
If your scabs are persistent or cause you concern, seek prompt medical care.
What other symptoms might occur with scabs?
Scabs may accompany other symptoms, which will vary depending on the underlying disease, disorder or condition. Symptoms that frequently affect the skin may also involve other body systems.
Skin symptoms that may occur along with scabs
Scabs may accompany other symptoms affecting the skin including:
- Bleeding or bruising
- Burning feeling
- Itchy skin
- Pain or soreness
- Pus or discharge
- Redness, warmth or swelling
- Thickening of the skin
- Tingling sensation
Other symptoms that may occur along with scabs
Scabs may accompany symptoms related to other body systems. These symptoms include:
- Malaise or lethargy
- Nausea with or without vomiting
- Nerve problems that cause pain, numbness or tingling
Serious symptoms that might indicate a life-threatening condition
Rarely are scabs a serious condition. However, any open wound can develop into a serious bacterial infection. Seek immediate medical care (call 911) if you, or someone you are with, have any of these life-threatening symptoms:
What causes scabs?
Scabs are a common symptom of skin infections, immune-mediated skin disorders, and injury. Scabs result from a growth of new skin over damaged skin as your skin attempts to heal.
Wounds or scratches due to viral skin infections, including cold sores (herpes simplex), chickenpox (varicella zoster), or shingles (herpes zoster), are common causes of scabs. Blisters, lacerations, abrasions or burns may also cause scabs as they heal. Impetigo, a bacterial skin infection, can also result in scabs.
Traumatic causes of scabs
Scabs may be caused by injury including:
- Insect bites
Disease causes of scabs
Scabs can also be caused by certain disease conditions including:
- Atopic dermatitis (eczema)
- Bacterial skin infection (impetigo)
- Chickenpox blisters or shingles (varicella zoster virus)
- Cold sores on your mouth and lips (Herpes simplex virus)
- Dermatitis artefacta (self-inflicted sores)
- Pemphigus vulgaris, fluid-filled blisters on your skin and mucus membranes (autoimmune disorder)
- Psoriasis lesions (immune disorder)
Serious or life-threatening causes of scabs
In some cases, scabs may be a symptom of a serious bacterial skin infection that should be immediately evaluated in an emergency setting. These include abscess and serious infection.
Questions for diagnosing the cause of scabs
To diagnose your condition, your doctor or licensed health care practitioner will ask you several questions related to your scabs including:
- Where do you have scabs?
- When did you first notice the scabs?
- Do you have scabs frequently?
- Do you have any other symptoms?
- What medications are you taking?
What are the potential complications of scabs?
Because scabs can be due to serious diseases, failure to seek treatment can result in serious complications and permanent damage. Once the underlying cause is diagnosed, it is important for you to follow the treatment plan that you and your health care professional design specifically for you to reduce the risk of potential complications including:
- Secondary bacterial infection
- Spread of infection