Plaque Psoriasis

Who's At Risk?

Plaque psoriasis is common, and it is estimated that 2%-3% of the US population has this condition. Plaque psoriasis can develop at any age, but it is usually diagnosed in the teenage or early adult years, and it is uncommon in infants. About 10%-15% of those affected start showing signs of the disease before age 10 years. About one-third of people with plaque psoriasis also develop psoriatic arthritis, an inflammatory joint condition that causes painful, swollen joints.

Plaque psoriasis affects males and females equally.

Signs & Symptoms

The typical lesions of plaque psoriasis are raised patches of irritated skin that are often covered with a thick, white scale. In lighter skin colors, the patches are most often pink or red. In darker skin colors, the redness may be harder to see or may appear purple, grayish, or dark brown.

Psoriasis patches are most frequently seen on the elbows, knees, trunk, buttocks, belly button, palms, soles, and scalp. The skin lesions are usually found on both sides of the body (symmetrically). Skin areas of physical trauma or friction may develop psoriasis plaques, which is why the hands / feet, scalp, knees, and elbows are commonly affected. Body folds such as the genitals or underarms may also be affected but tend to lack the classic thick, white scale often see in other body locations. Most individuals experience itching or skin / joint pain, but some may not.

Plaque psoriasis can be considered:

• Mild psoriasis – Few, scattered, limited areas of involvement that account for less than 10% of the body. To generally estimate body percentage involvement, the surface of a person’s palm print represents approximately 1% of their body surface area (ie, 3 palm prints of psoriasis lesions on the body is equal to approximately 3% of their body surface area). Topical or ultraviolet-based therapies are commonly used to treat mild psoriasis.
• Moderate-to-severe psoriasis – More widespread disease affecting larger areas of the body and account for at least 10% of the body. Individuals with these more severe forms of psoriasis often require more aggressive medical treatments in addition to or in lieu of topical therapies.
• Special considerations – Categorizing psoriasis solely on the percentage of affected skin has important limitations. Patients with psoriasis who have pain in the joints and/or involvement of certain skin sites (hands / feet, scalp, genitals, or face), even if the overall percentage is less than 10%, may require more aggressive treatment beyond topical medications due to the impact psoriasis can have involving these special sites of the body.

Other symptoms of psoriasis can include inflammation of tendons or ligaments, swollen fingers or toes, hair loss (alopecia), eye irritation (uveitis), or changes in the nails. Nails of the hands or feet may develop tiny pits or indentations, yellow-brown spots, or lifting up of the nail from the nail bed (onycholysis).

Importantly, plaque psoriasis if often confused with other skin conditions that can look similar, such as fungal infections of the skin, eczema (atopic dermatitis), allergic reactions, or irritation of skin exposed to specific environmental materials or products. Your medical professional may be helpful in determining the cause of your skin rash if the diagnosis is unclear.

Self-Care Guidelines

For mild and moderate plaque psoriasis:

• Have your child bathe daily to help soften the scale and moisten the skin. They should avoid harsh soaps and scrubbing the skin as these may worsen psoriasis. Moisturizing soaps and soap substitutes, such as unscented Dove Sensitive Skin Beauty Bar, Vanicream Cleansing Bar, and CeraVe Psoriasis Cleanser, are milder products for the skin.
• The application of moisturizers after water exposure or bathing may be helpful. Heavier, oilier moisturizers help to retain water in the skin better than water-based moisturizers. Thicker moisturizers such as petroleum jelly (Vaseline), Aquaphor Healing Ointment, Eucerin Original Healing Cream, Vanicream, Aveeno Moisturizing Cream, CeraVe Healing Ointment, or CeraVe Moisturizing Cream can be applied to damp skin daily after bathing. Use cream and ointments rather than lotions because lotions can dry out the skin.
• Apply over-the-counter hydrocortisone cream or ointment (0.5% or 1%) twice daily for 2-3 weeks at a time to help reduce itch and irritation. Stronger topical steroids are typically required for thicker psoriasis plaques. Long-term use of topical steroids should include periodic times of no treatment each month to avoid thinning of the skin.
• Coal tar products, available over the counter, can be used as a shampoo (eg, Neutrogena T/Gel Therapeutic Shampoo), oil, gel, or cream. This is an older form of therapy that can help, but it has a mild odor and can stain clothing.
• Use of products with salicylic acid (shampoos, cleansers, and ointments), such as Neutrogena T/Sal Therapeutic Shampoo, can help with removal of thick psoriasis scale in the scalp.
• Encourage your child to follow a healthy diet to maintain an ideal weight. (Being overweight may make plaque psoriasis worse.)

Small doses of natural sunlight may be helpful, such as 10-15 minutes 2 or 3 times a week. Avoid too much sun; however, and protect your child’s healthy skin from sun exposure.

Patient Support Resources
The National Psoriasis Foundation is a useful resource for patients and health professionals that has additional information regarding psoriasis and the various available treatments. The National Psoriasis Foundation website includes access to psoriasis-related articles, psoriasis research, a directory of health care professionals with an expertise in psoriasis, and opportunities for patients to volunteer or get involved in upcoming events.

Treatments

Unfortunately, there is no cure for plaque psoriasis, but there are many prescription-strength topical, oral, and injectable treatments that are helpful at controlling plaque psoriasis. For localized or mild psoriasis:

• The most common therapy for plaque psoriasis is topical steroids, either in cream or ointment form. Low- or mid-potency steroids, such as hydrocortisone 2.5% or triamcinolone, may be useful for thinner areas of skin (face or eyelids) or more sensitive body sites (armpits or genitals). Higher-potency topical steroids, such as clobetasol, halobetasol, or betamethasone, are used for the scalp, trunk, and extremities. Steroid solutions, foams, or liquids are very helpful for the treatment of scalp psoriasis. Use should be limited to twice-daily application for 2-3 weeks at a time followed by a 1-week break due to the possible development of stretch marks (striae) or thinning (atrophy) of the skin with long-term topical steroid use.
• Calcipotriene (Dovonex) is a nonsteroid vitamin D derivative cream that may help treat psoriasis plaques and is even more effective when combined with topical steroids.
• Tazarotene (Tazorac) is a vitamin A–based cream that may be prescribed to help reduce the inflammation, thickening, and scaling of the skin.
• Roflumilast (Zoryve) 0.3% cream is a nonsteroid cream recently approved for once-daily use in individuals aged 12 years and older and can be used safely on the face and skinfolds as well as other areas of the body.
• Coal tar–based therapies and anthralin (Drithocreme) creams are sometimes used, but they are used less frequently than other treatments because they have a foul odor, cause skin irritation, and can stain clothing, and because neither is any more effective than calcipotriene.

Treatment for more moderate-to-severe psoriasis or plaques involving special skin sites:

• If a large percentage of your skin is affected, ultraviolet (UV) light therapies may be considered. These include UVB phototherapy and PUVA (psoralen [a photosensitizer] and UVA therapy). PUVA may increase your risk for nonmelanoma skin cancers, and they may be less effective in darker skin colors.
• Injected (subcutaneous) or intravenous biologic therapies are one of the most common medicines used for plaque psoriasis. These are proteins that treat plaque psoriasis by blocking certain abnormal immune signals of the immune system that cause psoriasis. This class of medications is highly effective at treating psoriasis but may be costly if not covered by insurance. The number of injections each month, and the side effects differ for each medication and should be discussed with your medical professional. These medications include:
  • TNF-alpha inhibitors (eg, etanercept [Enbrel] in individuals 4 years and older)
  • IL-12/23 inhibitor (eg, ustekinumab [Stelara] in individuals 6 years and older)
  • IL-17 inhibitors (eg, secukinumab [Cosentyx] in individuals 6 years and older with plaque psoriasis and 2 years and older with psoriatic arthritis, ixekizumab [Taltz] in individuals 6 years and older).

Visit Urgency

See your child’s medical professional, such as a dermatologist or rheumatologist, for evaluation if self-care measures are not helpful, if the psoriasis is widespread, or if your child is experiencing joint or bone pain. Also see your child’s medical professional if their plaque psoriasis worsened or appeared after a sore throat, as plaque psoriasis can be triggered by a strep infection.

Individuals with psoriasis are also at increased risk for other health conditions such as heart disease, stroke, high blood pressure, diabetes, obesity, sleep problems, anxiety / depression, social stigma, and cancer. See your child’s medical professional to screen for these conditions.

Trusted Links

• National Psoriasis Foundation
• Clinical Information and Differential Diagnosis of Psoriasis
• Pack Health: Free one-to-one psoriasis health coaching

References

Bolognia J, Schaffer JV, Cerroni L. Dermatology. 4th ed. Philadelphia, PA: Elsevier; 2018.

James WD, Elston D, Treat JR, Rosenbach MA. Andrew’s Diseases of the Skin. 13th ed. Philadelphia, PA: Elsevier; 2019.

Kang S, Amagai M, Bruckner AL, et al. Fitzpatrick’s Dermatology. 9th ed. New York, NY: McGraw-Hill Education; 2019.

Paller A, Mancini A. Paller and Mancini: Hurwitz Clinical Pediatric Dermatology. 6th ed. St. Louis, MO: Elsevier; 2022.