What can cause sores or scabs on the scalp?
In this article, we look at the possible causes of sores or scabs on the scalp and their treatment options. We also cover prevention tips and when to see a doctor.
Image credit: Dermnet New Zealand
Image credit: CDC
Scab on the top of a person's head
Image credit: Klaus D. Peter, 2017
Image credit: Lforlav, 2011
Image credit: Kosta Y Mumcuoglu, 2007
Image credit: Amras666, 2008
Psoriasis is a condition where the body replaces skin cells much faster than normal, which causes dry, red, and scaly patches of skin. These patches can occur almost anywhere on the body, including the scalp.
Special shampoos, especially those containing coal tar, may help. Doctors can also prescribe oral and topical medications to help relieve symptoms and prevent flare-ups.
Some people with psoriasis find that certain things trigger or worsen their symptoms. Identifying and avoiding these triggers, which may include stress or certain foods, can help.
Contact dermatitis is a type of eczema that causes dry, red, and blistered skin. It occurs when an irritating substance comes into direct contact with a person's skin. When contact dermatitis develops on the scalp, the irritating substance is often a shampoo, hair product, or soap.
Contact dermatitis usually clears up on its own once a person identifies and avoids the irritant. If the rash is very painful or itchy, a doctor may prescribe a medicated shampoo or corticosteroid to relieve symptoms.
A minor injury to the scalp can cause a cut or scrape. A person can usually treat small cuts and scrapes at home, but if the wound is large and painful, it may require medical care. Avoiding irritants, such as shampoo and styling products, may help speed up healing.
Infected scalp injury
An injury to the scalp can become infected, causing painful scabs, blisters, and swelling. Signs of infection can include:
- pain or tenderness around the injury
- red streaks coming out of the injury
- slow healing
To ensure a quick recovery and to reduce the risk of complications, it is important to see a doctor for a suspected infection. Most bacterial infections respond well to antibiotics.
Impetigo is a bacterial infection of the skin that causes blisters and sores. The sores can be itchy and typically appear on the face and mouth but can sometimes develop on the scalp or hairline.
Impetigo can occur after Staphylococcus or Streptococcus bacteria enter a cut or wound. The infection is highly contagious and is common among young children.
Although mild impetigo may clear up on its own, prompt treatment is still critical. A doctor can prescribe topical or oral antibiotics to help:
- prevent the infection from getting worse
- reduce the risk of passing the infection to others
- reduce the risk of complications
Folliculitis is an infection of the hair follicles that can cause acne-like pimples or crusty sores. This condition is common after hair removal, especially by shaving.
Mild folliculitis often clears on its own, but it is best to avoid shaving the head until the symptoms clear up. If folliculitis is painful or gets worse, a doctor may prescribe an antibiotic treatment.
For people who shave their heads, the following may help prevent folliculitis on the scalp:
- exfoliating the scalp before shaving
- wetting the skin and using a cream or gel before shaving
- always using a clean, sharp razor
- applying an aftershave treatment
Acne is a skin condition that can cause pimples and other lesions to develop in body areas where there are hair follicles, including the scalp. Acne typically occurs when hair follicles become clogged with oil, dead skin cells, and bacteria, so people with oily hair may be more likely to develop acne on the scalp.
Scalp acne often clears up on its own, but severe cases may affect hair growth or cause pain. People should avoid picking or scratching pimples as this can worsen symptoms or lead to further breakouts.
A person can treat scalp acne at home with medicated shampoos and regular hair washing. For severe or persistent acne, a doctor may prescribe acne medications or antibiotics.
Head lice are tiny bugs, smaller than a grain of rice, that live in human hair. They lay their eggs near the bottom of the hair shaft and survive by feeding on tiny amounts of blood from the scalp.
Over time, these eggs hatch and create larger and larger infestations. Head lice are highly contagious, especially among children who come into close contact with each other or share brushes and hair care products.
Head lice can cause intense itching. Scratching the scalp can cause sores and scabs that make the itching even worse. It is possible for these sores to become infected, which may require antibiotic treatment.
People can treat head lice at home with medicated shampoos and by using special combs to kill lice and remove their eggs from the hair. It may take several treatments to get rid of a head lice infestation completely. For the most success, it is best to follow the instructions that come with head lice products carefully.
Seborrheic dermatitis is a common condition that causes red, itchy, and flaky skin. This rash often occurs on the scalp or near the hairline.
Seborrheic dermatitis can appear greasy or scaly and in severe cases can cause raised bumps around the hairline. Scratching the rash can cause injuries to the scalp.
Infants often get a type of seborrheic dermatitis called cradle cap. Cradle cap usually clears on its own by the child's second birthday. Moisturizing the infant's scalp and gently massaging the affected area may help ease symptoms.
In adults with seborrheic dermatitis, stress or other triggers may cause symptoms to reoccur frequently. Identifying and managing these triggers can help prevent flares. Using antifungal shampoos and topical steroid creams may also be useful.
If seborrheic dermatitis becomes infected due to frequent scratching, a doctor may prescribe antibiotics.
Cysts are fluid-filled sacs that can develop just below the skin. They can vary in size and may feel sore or tender. Cysts that develop on the scalp are usually trichilemmal cysts.
As a cyst grows, it may burst, causing sores and scabs. Frequently touching or trying to pop a cyst can damage the skin, which can also lead to sores and scabs, as well as infections. Cysts often develop after an injury to the skin and can also occur when oil clogs a hair follicle.
Cysts that burst tend to refill and come back. Treating them at home with warm compresses may help the cyst drain more quickly. If a cyst is causing problems, a doctor can remove it.
A person should also see a doctor if a cyst becomes infected. Antibiotics may be necessary to treat an infected cyst.
Many causes of sores and scabs on the scalp, such as psoriasis, are not contagious. And while medications and lifestyle remedies can help control symptoms of skin conditions, including psoriasis and seborrheic dermatitis, they cannot prevent them entirely.
Some other causes of scalp sores are preventable. A few strategies include:
- making children wash their hands regularly and avoid close contact with children who have infections
- washing hair regularly to prevent acne and reduce the risk of scalp infections after an injury
- avoiding excessively touching or scratching the scalp
- using shampoo that does not irritate or dry the scalp
- seeing a doctor for scalp problems that do not go away on their own
When to see a doctor
Scabs and sores on the scalp are often harmless and will clear up on their own without treatment. However, people should speak to a doctor if the scabs or sores:
- are very painful or itchy
- do not start clearing up after a few days
- keep reoccurring or get worse
- are on a young child's head
People should also speak to a medical professional, as soon as possible, if:
- a fever develops
- the scalp becomes swollen
- there are signs of infection, such as red streaks coming from the sores
- the person with scabs or sores is on dialysis or receiving cancer treatment
There are many possible causes of sores or scabs on the scalp. While many lesions on the scalp are harmless, some can be the sign of an underlying medical condition.
See a doctor for sores and scabs that do not clear up on their own, keep reoccurring, or are very painful or itchy. A person should seek prompt medical attention if they suspect the scabs and sores may be infected.