A frequent question asked by visitors to HealthCentral is about unexplained rashes.
Although there can be a multitude of possible causes for a rash, sometimes it is a symptom of a chronic skin condition. Two chronic skin disorders which begin with a rash include eczemaand psoriasis. But how can the average person know the difference between the two?
To answer this question, we enlisted the help of Dr. Lawrence Green, a practicing dermatologist and assistant clinical professor of dermatology at George Washington University School of Medicine in Washington DC, to discuss the similarities and differences between eczema and psoriasis.
To find out more about Dr. Green, visit his website: Aesthetics, Skin Care, and Dermasurgery.
Question: What are the differences in symptoms between eczema and psoriasis? How can the average person tell the difference?
Dr. Green: Psoriasis and eczema can look the same because they are both rashes, and they both itch, but they are actually very different conditions. Psoriasis usually starts in teenage years or later, while eczema starts in childhood. Psoriasis is usually on the scalp, elbows, and knees (although it can be anywhere), while eczema is usually in the creases of skin, such as the neck or eyelids, or creases in the arm and leg opposite the elbows and knees. Also, psoriasis is usually thicker and has bigger scales of skin shedding then eczema.
Question: Are there similarities between these two skin conditions?
Dr. Green: Both psoriasis and eczema are genetic, autoimmune diseases, meaning they are thought to be inherited and are caused by immune system over-activity. But eczema is propagated by a different subtype of immune system cell over-activity than the ones propagated by psoriasis.
Question: Can either eczema or psoriasis be treated with over-the-counter products or should a person go see a dermatologist?
Dr. Green: Moisturizing creams and ointments (but not lotions) can help improve the symptoms of both psoriasis and eczema, but will not actually treat these conditions. You usually do need to see a dermatologist to get prescriptions for medications that do that.
Question: What can a dermatologist do to treat eczema or psoriasis?
Dr. Green: A dermatologist can prescribe medications to help control both conditions. These can be ointments, ultraviolet light boxes, or pills. For psoriasis, we can also use injectable medications, if the need arises.