Eczema: intensely itchy red patches in the skin folds, starting in childhood. Psoriasis: thick, sharply edged plaques with silvery scale on elbows, knees, scalp, and back, usually starting in adulthood, sometimes with pitted nails and stiff joints.
The three-axis split: itch (ferocious in eczema, milder in psoriasis), look (weepy or leathery with blurry borders vs silvery and sharply demarcated), and location (folds vs outer surfaces). Triggers differ: eczema flares with irritants, fragrance, dry air, and sweat; psoriasis with skin injury, stress, strep infections, and some medications. Shared ground: neither is contagious, moisturizers are the foundation for both, and both treat well, eczema with trigger avoidance and topical steroids, psoriasis with topicals, light therapy, and biologics for moderate-to-severe disease. The dermatologist lines: a first widespread rash, no response to basic care in weeks, joint pain with a scaly rash (psoriatic arthritis is a real complication), or infection signs like honey-crusted ooze and spreading redness.
What to do
Common questions
What is eczema vs psoriasis?
They are both chronic inflammatory skin conditions, and they are easy to tell apart once you know the three axes: itch, look, and location. Itch: eczema's hallmark is ferocious itching, the itch that rashes, often worse at night and strong enough to disturb sleep; psoriasis can itch or burn but usually mildly. Look: eczema patches are red, dry, sometimes weepy or crusted when flaring, and leathery-thickened from chronic scratching, with blurry borders; psoriasis plaques are thick, sharply demarcated, and covered in silvery-white scale, per MedlinePlus's descriptions of both. Location: eczema favors the folds, inner elbows, behind the knees, the neck, and (in babies) the face; psoriasis favors the outer surfaces, elbows, knees, scalp, lower back, and it loves symmetry, plus it can pit the nails (tiny dents) and stiffen the joints (psoriatic arthritis, a real complication eczema does not have). Timing: eczema usually starts in childhood and often improves with age; psoriasis typically appears in adulthood and runs a lifelong relapsing course. Triggers differ too: eczema flares with irritants, fragrances, dry air, sweat, and stress; psoriasis flares with skin injury, stress, infections (especially strep), cold dry weather, and some medications. What they share: neither is contagious, both respond to moisturizers as a foundation, and both treat well: eczema with trigger avoidance plus topical steroids, psoriasis with topical steroids and vitamin D creams, light therapy, and for moderate-to-severe cases the modern biologics that have transformed it. The see-a-dermatologist lines: a first widespread rash (diagnosis matters before months of wrong cream), anything not responding to basic care in a few weeks, joint pain or stiffness with a scaly rash, or signs of skin infection (oozing honey-colored crusts, fever, spreading redness).