Psoriasis is a common, long-lasting condition that primarily affects the skin, causing cells to build up quickly on the surface. It is considered an immune-mediated disease. This condition is not contagious, so you cannot catch it from another person through contact. While there is currently no cure, psoriasis is highly manageable through various treatments, and many people experience cycles where symptoms flare up and then subside.
The Immune System and Cell Turnover
Psoriasis develops because of a mistaken response within the body’s immune system. Infection-fighting cells, specifically a type of white blood cell called T cells, become overly active and incorrectly attack healthy skin cells. This misdirected attack triggers inflammation within the skin layers.
This inflammation dramatically accelerates the production cycle of new skin cells. Typically, a skin cell takes about 28 to 30 days to travel from the bottom layer to the surface and shed. With psoriasis, this process is sped up to only three to seven days. Because the cells reach the surface so rapidly, they do not have time to mature properly, causing them to pile up instead of flaking away naturally. This rapid accumulation creates the characteristic thickened, scaly patches seen on the skin.
Visualizing Psoriasis on the Skin
The most recognizable sign of psoriasis is the development of skin patches called plaques. On lighter skin tones, these patches typically appear red or pink with silvery-white scales. For people with darker skin, the plaques may look more violet, purple, or dark brown with gray scales.
These plaques are often symmetrically distributed and most commonly appear on the elbows, knees, lower back, and scalp. The affected areas can cause uncomfortable sensations such as itching, burning, or stinging. Plaque psoriasis is the most frequent type, but other forms exist, such as guttate psoriasis, which presents as small, drop-shaped spots. Inverse psoriasis appears as smooth, red patches in skin folds like the armpits or groin, where moisture prevents the formation of thick scales.
Modern Treatment Approaches
Managing psoriasis involves a stepped approach that aims to slow down rapid skin cell growth and reduce inflammation. Initial treatment for mild or localized cases involves topical therapies applied directly to the skin. These include medicated creams and ointments, such as corticosteroids and vitamin D analogs, which help reduce redness, swelling, and scaling.
If topical treatments are insufficient, a healthcare provider may recommend phototherapy, which involves controlled exposure to ultraviolet (UV) light. Narrowband UVB phototherapy works by calming the overactive immune response in the skin. This treatment is typically administered in a clinic several times a week.
For moderate to severe psoriasis, systemic medications are often necessary. These treatments work internally to target the immune system and include traditional oral medications and advanced biologic therapies. Biologics are protein-based drugs administered by injection or infusion that specifically block the inflammatory pathways driving the disease. These targeted treatments have shown success in clearing the skin.
Systemic Impact and Related Conditions
Psoriasis is a systemic inflammatory disease that affects more than just the skin. The chronic inflammation can impact other parts of the body, leading to related health issues called comorbidities. One of the most common is psoriatic arthritis, which affects up to 30% of people with psoriasis and causes pain, stiffness, and swelling in the joints.
Psoriasis is also linked to an increased risk of other serious health concerns, including cardiovascular disease, high blood pressure, and obesity. The visible nature of psoriasis and the discomfort it causes can take a toll on mental health, leading to higher rates of depression and anxiety. Treating the skin condition effectively can help lower the risk of these associated comorbidities.