Psoriasis is a chronic inflammatory condition that affects the skin. The skin on the elbows, knees and scalp are most commonly affected in psoriasis. Psoriasis is characterized by the appearance of symmetrical red patches with silvery scales on the affected skin areas. There may also be visible changes in the nails, such as pitting, nail thickening and separation of the nails from the nail beds. Even joints may be affected in psoriasis. There is no cure for psoriasis. However, the disease has alternating periods of remission and exacerbation.
What is Scalp Psoriasis?
Scalp psoriasis may either occur on its own or be present along with some other generalized skin condition. It is estimated that as many as 50% of the people who suffer from psoriasis also have scalp psoriasis. Scalp psoriasis may affect the skin on any region of the scalp. However, it usually affects the scalp at the back of the head. Scalp psoriasis is characterized by isolated red patches of skin with thick and silvery scales.
These patches may even extend beyond the hairline. The thick, silvery scales tend to be flaky, and can be mistaken for dandruff. If one tries to remove the scaly patches on the skin, they may bleed. The skin patches in scalp psoriasis are extremely itchy. This intense itchiness may be a cause for social embarrassment. Scalp psoriasis can also lead to temporary hair loss in a localized manner. However, permanent balding is rare.
Complications of Scalp Psoriasis
Scalp psoriasis may lead to some of the following complications:
- Hair loss: Scalp psoriasis may lead to temporary hair loss. Permanent hair loss is rare, but can occur if infection is also present.
- Spread of psoriasis to other regions of the body: Psoriasis may also flare up in additional parts of the body (such as psoriatic arthritis and pustular psoriasis).
- Secondary infections: Secondary infections may occur in the psoriatic skin patches.
- Social awkwardness: The intense itching and other symptoms associated with scalp psoriasis may cause social embarrassment, leading to loss of self-esteem and depression.
- Side-effects of treatment: Drugs used to treat scalp psoriasis can cause severe side-effects.
Conditions Similar to Scalp Psoriasis
Some other skin conditions that cause an itchy scalp may be mistaken for scalp psoriasis. A thorough physical examination to check for psoriasis in other parts of the body can help in differentiating scalp psoriasis from other similar conditions. Scalp psoriasis can be confirmed through a skin biopsy.
Seborrheic dermatitis of the scalp
Seborrheic dermatitis is an itchy skin condition that occurs in the body areas with high sebum production (such as face, back, and chest). The affected skin areas in seborrheic dermatitis are reddish, oily and scaly. The scaly skin is also flaky, and white or yellow in color.
When seborrheic dermatitis affects the scalp, the condition is popularly known as dandruff. The skin lesions in seborrheic dermatitis of the scalp are itchy and scaly, with thick crusts that can be removed easily. The affected skin patches are usually restricted to the hairline. Seborrheic dermatitis of the scalp does not result in permanent hair loss. In newborns, seborrheic dermatitis of the scalp manifests as “cradle cap”.
Sebopsoriasis refers to a condition in which both psoriasis and seborrheic dermatitis co-exist in an individual. Unlike in psoriasis, the scales on the affected skin patches in sebopsoriasis are yellowish rather than silvery. In this condition, the skin on the scalp is similar to that in seborrheic dermatitis, with a deep reddish color and thick scales. The skin patches in sebopsoriasis have more defined edges than the skin patches in seborrheic dermatitis.
Tinea capitis is a fungal infection of the scalp. Also known as scalp ringworm, tinea capitis is a highly contagious infection. The affected areas of skin on the scalp appear as reddish or grey patches that are itchy and scaly. There may also be areas on the scalp that are painful. Bald patches may appear on the scalp, and expand with time. These patches show small dots in places where the hair has broken off. Tinea capitis is relatively more common in children.
Lichen planus is another itchy skin condition that affects the scalp, in addition to other areas such as the forearms, wrists, nails, oral cavity, anus and vagina. Purple or reddish-purple bumps with flat tops and uneven margins appear on the affected skin areas. The skin lesions in lichen planus are itchy, and may also have scales or white flakes. Unlike in scalp psoriasis, lichen planus of the scalp can lead to permanent hair loss. Clusters of hair follicles may be surrounded by tiny, red swellings. Permanent bald patches, with or without inflammation or scaling, may appear.
Eczema is characterized by reddish, dry skin that is likely to have itch intensely. Blisters and oozing lesions may also be present in some cases. Eczema can affect the skin in any part of the body. Children are more prone to getting scalp eczema.
Read more on scalp problems.
Treatment of Scalp Psoriasis
There is no permanent cure for psoriasis. However, treatments may provide relief from symptoms and help in remission. Treatment for scalp psoriasis can be categorized into the following three types:
- Topical treatment: For most cases, topical therapy is the main line of treatment. In mild or moderate cases of scalp psoriasis, topical applications may be the only therapy given. In some cases, topical therapy may be combined with phototherapy. Topical applications are usually in the form of medicated shampoos, gels, ointments, or foam and oil-based preparations. These preparations may contain corticosteroids, retinoids, vitamin D analogs, anthralin, calcineurin inhibitors, coal tar, salicylic acid, emollients and moisturizers.
- Phototherapy: Phototherapy involves exposure of the affected skin areas to sunlight, ultraviolet B, and excimer or pulsed dye laser. The head may need to be shaved for phototherapy to be effective.
- Medicines: Drugs to treat scalp psoriasis are given only if the condition is persistent or is widespread on the body. The drugs may either be oral formulations or injections. Drugs used in the treatment of scalp psoriasis include methotrexate, retinoids, hydroxyurea, cyclosporine, thioguanine and immunomodulators. These drugs are used as the last resort because they produce many side-effects.