skin-concerns
What Is Psoriasis?
Last reviewed: May 2026 · Haute MD Editorial Team
Psoriasis is a chronic autoimmune condition in which the immune system triggers accelerated skin cell turnover — cells that normally take 28-30 days to mature and shed do so in 3-5 days, producing the characteristic thick, silvery-scaled plaques. It affects approximately 8 million Americans and is associated with psoriatic arthritis in 20-30% of patients, as well as increased cardiovascular risk in severe disease. Modern biologic therapies have transformed outcomes — complete or near-complete clearance is now achievable for the majority of patients with moderate-to-severe psoriasis.
Types of psoriasis
Plaque psoriasis is the most common type (90% of cases) — raised, red patches covered with silvery-white scales, most commonly on elbows, knees, scalp, and lower back. Guttate psoriasis presents as small, drop-shaped lesions often triggered by streptococcal infection — more common in children and young adults. Inverse psoriasis occurs in skin folds (under breasts, groin, armpits) — smooth, red patches without typical scaling. Pustular psoriasis presents with pus-filled blisters. Nail psoriasis causes pitting, discoloration, and separation of the nail.
Triggers and lifestyle management
Common psoriasis triggers include streptococcal throat infection (particularly for guttate flares), skin injury (Koebner phenomenon — new plaques at injury sites), stress, certain medications (lithium, beta-blockers, antimalarials), alcohol, and smoking. Alcohol and smoking both worsen psoriasis severity and reduce treatment response. Sun exposure in moderated amounts often improves plaque psoriasis. Maintaining a healthy weight reduces psoriasis severity — adipose tissue produces inflammatory cytokines that worsen the condition.
Treatment options from topicals to biologics
Mild psoriasis — topical corticosteroids, vitamin D analogues (calcipotriol), retinoids (tazarotene). Moderate psoriasis — phototherapy (narrowband UVB), methotrexate, cyclosporine, apremilast (Otezla). Severe psoriasis — biologic medications targeting specific immune pathways. IL-17 inhibitors (secukinumab, ixekizumab, bimekizumab) and IL-23 inhibitors (guselkumab, risankizumab, tildrakizumab) produce the highest clearance rates — 80-90% of patients achieve 90% skin clearance (PASI 90) in clinical trials.
Frequently Asked Questions
Is psoriasis contagious?
No. Psoriasis is an autoimmune condition — not an infection. It cannot be transmitted by any form of contact.
What is psoriatic arthritis?
Psoriatic arthritis is an inflammatory arthritis occurring in approximately 20-30% of people with psoriasis. It causes joint pain, swelling, and stiffness — most commonly in fingers, toes, wrists, and the lower back. Many biologics treat both skin and joint disease simultaneously. Early treatment prevents joint damage.
Do biologics for psoriasis require injections?
Most biologic medications for psoriasis are self-administered by injection (subcutaneous) at home. Injection frequency varies by medication — some are monthly, others every 8-12 weeks after an initial loading period.
Can psoriasis affect the scalp and nails?
Yes. Scalp psoriasis affects approximately 50% of patients and can cause significant itching, scaling, and hair loss (typically temporary). Nail psoriasis affects 50-80% of patients at some point — causing pitting, discoloration, thickening, and nail separation. Both are challenging to treat and may benefit from systemic therapy.
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