Scabs on Scalp: 9 Common Causes & What to Do

Scabs on the scalp can emerge due to folliculitis, dermatitis, psoriasis or an allergic reaction to chemical products, like hair dye or or hair treatments. It is rare for scabs to form due to severe health conditions, like skin cancer. 

To identify the underlying cause, you should see a dermatologist to assess your scalp. The doctor may order further testing to reach a diagnosis and to guide the most appropriate treatment approach. 

Generally, treatment usually involves scalp-specific interventions, like regularly washing the scalp, using hats with wet hair, and using specific shampoos or ointments that reduce inflammation or speed-up healing. The doctor may prescribe topical antifungals or corticosteroids, for example. 

Common causes

The most common causes of scabs on the scalp include: 

1. Excess dandruff

Excess dandruff, also known as seborrheic dermatitis, is a skin inflammation that causes flaking, redness and scabs. The scabs look like white crusts and can itch and form in other areas, like the face, eyebrows, ears and nose. 

Although the underlying cause is not totally known, this condition has a chronic evolution with periods of improvement and worsening. Dandruff can be triggered by emotional stress, allergies, scalp oil, alcohol, certain medications or a fungal infection from Pityrosporum ovale.

What to do: You should see a dermatologist for treatment to control the formation of these scabs and prevent hair loss. The doctor may prescribe shampoo or ointments with antifungals, or corticosteroids like salicylic acid, selenium, sulfur or zinc. 

You should also stop using any hair products, particularly those that leave your hair more oily. You should also avoid frequently washing your hair and using hats. Check out these home remedies for dandruff that you can use to manage and prevent mild dandruff. 

2. Fungal scalp infection 

Fungal scalp infections are most commonly caused by Tinea capitis fungus and fungi in the Trichophyton e Microsporum species. They most commonly affect children. 

Tinea capitis fungus affects hair strands and follicles and usually cause circular, flaking and red wounds with yellow crust. These fungal wounds often lead to hair loss. 

What to do: Treatment should be oriented by a dermatologist and may involve antifungals like terbinafine and griseofulvin, taken for 6 weeks. In addition, shampoos with sulfates, selenium or ketoconazole may help to eliminate the infection. 

3. Allergic reaction

Some chemical products can cause an allergic skin reaction that leads to scabs on the scalp. Scabs can also be caused by permanent straightening or curling products, like ammonium hydroxide or formaldehyde. Scabs can also be caused by any other substances an individual is allergic to. 

Scalp scabs can emerge within hours or days after initial contact with the product. Some people may also notice flaking, redness, itching or burning in the area. 

What to do: The first step is to identify the allergy trigger, so that this product can be avoided and eliminated from your day-to-day routine. A dermatologist may prescribe oral or topical corticosteroids, as well as anti-inflammatory and healing lotions to be applied directly to the scalp. 

In addition, when using chemical hair products, you should avoid direct contact of the product with the scalp to reduce the chances of irritation and dryness. 

4. Folliculitis

Folliculitis is an inflammation of the hair root which is usually caused by a bacterial or fungal infection. It can cause red, pus-filled bumps that are painful, burn and itch. This condition can even lead to hair loss.

What to do: Treatment should be oriented by a dermatologist, who may recommend antifungal shampoos (with ketoconazole, for example) or antibiotic treatment (with erythromycin or clindamycin). Learn more about the folliculitis treatment that your doctor may consider. 

5. Lice infestation

A lice infestation is most common in school-aged children, and is characterized by the growth and spread of small parasites that live and feed off the scalp. 

Lice bites can cause small inflamed pinpoints on the skin. These pinpoints can lead to scabs that itch and crust up.  

What to do: To eliminate lice, you should use lice-specific shampoos, fine tooth combs and antiparasitic medications, like ivermectin. If the scabs become infected, the doctor may also prescribe antibiotics. 

To prevent lice, you should avoid sharing brushes, hats and glasses. You should ideally tie your hair back when in large groups of people. There are also repellent sprays that you can purchase at the pharmacies and apply to your hair. Learn more about how to get rid of lice naturally as a compliment to medicated treatments. 

6. Psoriasis on the scalp 

Psoriasis is a chronic inflammatory disease related to changes in the immune system, It can cause red rashes with intense flaking and white or gray scabs.

Psoriasis can affect the skin as well as the nails (which become thick and loose) and is associated with symptoms like joint pain and swelling. Psoriasis on the scalp can cause intense itching and flaking, similar to dandruff, as well as hair loss. 

What to do: Treatment for psoriasis should be done as recommended by a dermatologist or rheumatologist. It may involve lotions with corticosteroids (like betamethasone), salicylic acid or clobetasol propionate. Adhering to a psoriasis diet can help to reduce symptom intensity and prevent flare-ups in the future. 

7. Lichen planus

Lichen planus is an inflammatory disease that can affect the skin, nails, scabs, oral mucosa and genitals. 

This disease is characterized by the appearance of red lesions that look like white, wrinkled stretch marks that have a characteristic shine to them. These lesions can itch very intensely and swelling.

What to do: Treatment for lichen planus should be oriented by a dermatologist and usually involves medication that relieves itching, like antihistamines and topical corticosteroids.

8. Scleroderma

Scleroderma is a chronic autoimmune disease related to excess collagen production, It leads to thickening of the skin and affects the joints, muscles, blood vessels and some organs, like the lungs and heart. 

The main symptoms of scleroderma are hair loss, constant itching, dark and light-colored rashes, as well as thickening and rigidity of the skin. 

What to do: There is no cure for scleroderma, although treatment can help to prevent progression, relieve symptoms, and improve quality of life. 

9. Lupus

Lupus is an autoimmune disease characterized by the production of antibiotics that attack healthy cells in the body. IT can cause inflammation in many areas, such as the skin, face and scalp.  

The main symptoms of lupus are hair loss (due to thinning of the hair), as well as hair loss in the bead, eyebrows and eyelashes. 

What to do: Treatment for lupus should be oriented by a rheumatologist and may include the use of anti-inflammatories, corticosteroids or immunosuppressants. Treatment is aimed at relieving symptoms and reducing immune system responses.