Eczema vs. Psoriasis

Understanding the similarities and differences

Young female doctor examining psoriasis on hand of an senior woman patient in a doctor's office. Could be used also as Homeopathy Interview. Selective focus to senior woman.
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Both eczema and psoriasis are chronic skin diseases that cause red, scaly skin rashes. Though they are quite similar, the range of symptoms for each is usually different enough for your doctor to tell them apart without doing a skin biopsy or other diagnostic testing. 

Where Eczema Usually Occurs

Eczema tends to affect the hands, feet, and nape of the neck. It also favors the inside of the arms and the back of the knees, called flexor surfaces.

Both eczema and psoriasis rashes appear frequently on the scalp, while chronic eczema is found on the ankles more often than psoriasis.

Eczema Symptoms

Signs and symptoms of eczema, also called atopic dermatitis, vary widely from person to person and may include:

  • Itching, which may be severe, especially at night
  • Red to brownish-gray patches, especially on the hands, feet, ankles, wrists, neck, upper chest, eyelids, inside the bend of the elbows and knees, and, in infants, the face, and scalp
  • Small, raised bumps which may leak fluid and crust over when scratched
  • Thickened, cracked, dry, scaly skin
  • Raw, sensitive, swollen skin from scratching

Eczema most often begins before age 5 and may persist into adolescence and adulthood. For some people, it flares periodically and then clears up for a time, even for several years.

Where Psoriasis Usually Occurs

Like eczema, psoriasis tends to affect the hands, feet, and nape of the neck.

Psoriasis also likes to involve the back of the elbows and front of the knees, called extensor surfaces. If they're there, pustules or blisters on the palms of the hands and soles of the feet can help distinguish between psoriasis and eczema. Psoriasis sometimes has them, but eczema usually does not.

Psoriasis Symptoms

Psoriasis signs and symptoms can vary from person to person but may include one or more of the following:

  • Red patches of skin covered with silvery scales
  • Small scaling spots (commonly seen in children)
  • Dry, cracked skin that may bleed
  • Itching, burning, or soreness
  • Thickened, pitted, or ridged nails
  • Swollen and stiff joints

How to Tell Which is Which

Psoriasis patches can range from a few spots of dandruff-like scaling to major eruptions that cover large areas. The rash of psoriasis is well-demarcated, meaning it has a very clear border separating it from the skin that's not affected, while eczema's border is less well-demarcated, meaning it's harder to see the separation. Most types of psoriasis go through cycles, flaring for a few weeks or months, then subsiding for a time or even going into complete remission.

Hands and feet are the most difficult areas to tell psoriasis and eczema apart. For one thing, the fungus may be along for the ride as well. Even a biopsy of hand and foot rashes may show confusing overlap, causing pathologists to hedge a bit and give a non-specific reading or report.

One small clue to psoriasis of the hands is that nails will show pitting. Nail changes also occur in eczema and fungus cases, but pitting—especially in a nail where the cuticle is not involved with any rashes—is fairly uncommon.

Treatment

Some treatments work for both psoriasis and eczema, though others are quite specific. If you think you have either eczema or psoriasis, it's important to see a dermatologist so that your rash can be assessed and you can get the most effective treatment.

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