Psoriasis: Start Here Before Calling Every Scaly Rash Eczema
Psoriasis can affect skin, scalp, nails and joints. This guide highlights the clues that change diagnosis and treatment planning.
Psoriasis · 8 min read · August 22, 2026
Psoriasis is more than dry skin
Psoriasis is a chronic inflammatory disease that can produce thick plaques and scale, but its appearance varies by skin tone and body site.
Places that give extra diagnostic clues
- Scalp: thick scale can extend beyond the hairline.
- Nails: pitting, discoloration, separation or thickening.
- Skin folds or genitals: plaques may show less scale.
- Joints: pain, swelling or persistent morning stiffness can suggest psoriatic arthritis.
How treatment is chosen
Treatment depends on severity, body surface area, location, quality-of-life impact and whether nails or joints are involved. Options can include topical treatment, phototherapy, systemic medicines or biologic therapy in selected patients.
The clue not to ignore
Joint pain, swelling or persistent morning stiffness alongside psoriasis should not be treated as a skin issue alone. Early assessment can matter for long-term joint health.
Medical references
Medical review
This guide was written and medically reviewed by Dr. Yousef Abo Zarad, a German board-certified specialist in Dermatology and Venereology.