How do I Know if it’s Eczema or Psoriasis?
Eczema and psoriasis are two different skin conditions that may appear similar, but are essentially different.
Psoriasis is a result of an overactive immune system, causing skin cells to grow rapidly. These cells pile up on the surface of the skin leading to dry, flaky plaques or scales.
Most types of psoriasis can be triggered by cold weather, infection, medications, skin injury, and stress. Genetics also seem to play a role as psoriasis tends to run in families.
Likewise, while the exact cause of eczema is unknown, it is believed that an overly-reactive immune system can get triggered by a substance inside or outside the body resulting in skin inflammation. According to research, some people with eczema have a gene mutation in the skin barrier, leaving the skin more vulnerable to allergens, dryness, and irritants. And just like with psoriasis, stress can also trigger eczema and family history can increase the risk of developing this skin condition.
Diagnosing Eczema and Psoriasis
Some dermatologists can diagnose eczema or psoriasis after visual assessment.
However, since most skin diseases tend to look the same, additional tests are needed to confirm the diagnosis. They will ask you questions about your general health, symptoms you experienced, and allergies you have.
A patch test can help determine if you have any allergies. For this test, the doctor would apply small amounts of different allergens and irritants to your skin and cover each area with a patch. You will be asked to return 2 days later to remove the patches.
On your third visit, the skin would be examined once again for reactions, after which, the dermatologist would be able to determine what medication to give you and advise which substances to avoid.
The doctor may also require skin biopsy for further assessment. During a skin biopsy, a small sample of skin tissue is removed. This sample is then sent to a lab for analysis. A skin biopsy can help diagnose eczema and psoriasis, as well as rule out similar conditions.
There are also cases wherein it is difficult to tell the difference in spite of the tests
conducted. A person may also have both eczema and psoriasis. In this situation, a
dermatologist might diagnose the patient with “psoriasiform dermatitis.”
Still, an experienced dermatologist would generally be able to differentiate between these two relatively common skin disorders.
The following additional signs may indicate psoriasis instead of eczema:
- Psoriasis does not occur often in infants, but when it does affect this age group, it appears as bright red, well-defined patches with no scaling on the diaper area.
- On the other hand, it is not unusual for children to have psoriasis. The outbreak is often preceded by an infection, and the patches are spread out over the body. This condition is referred to as guttate psoriasis.
- In adults, psoriasis affects different areas of the body, particularly the scalp (dry dandruff), elbows (in eczema, it’s in the elbow folds), fingernails (thick and dented), buttocks, and front of the knees (in eczema, it’s on the back of the knees).
Triggers for Eczema and Psoriasis
While both skin conditions are chronic, they can flare up from time to time in response to different triggers.
Eczema is triggered more by things you come into contact with, like certain perfumes, nickel, pollen, or preservatives. For some, cigarette smoke, dust, mold, polyester, wool, and sometimes hormones can kick off eczema flares.
Conversely, psoriasis can be triggered by alcohol, infections like strep throat, certain medications, scratches, skin injuries, and sunburns.
Dry weather and stress tend to be triggers for both eczema and psoriasis.
People with psoriasis may be able to relieve mild-to-moderate discomfort and reduce dryness and itchiness by keeping the skin clean and moisturized. It is best to avoid harsh soaps and hot baths and showers.
The doctor may prescribe one of the following medications to treat moderate to severe psoriasis:
- Anthralin - slows the accelerated growth of skin cells
- Coal tar - reduces inflammation and scaling
- Salicylic acid - removes the scaling of skin, enabling other medications to penetrate the skin better
- Synthetic vitamin D - flattens raised areas, slows skin cell growth, and removes scaling
- Topical corticosteroids - reduces inflammation and itching
- Topical retinoid - slows skin cell growth
Injectable and oral medications are also available if topical medicines don’t work.
Examples are cyclosporine (Gengraf), immune-modulating drugs, such as apremilast (Otezla), methotrexate (Trexall), and oral retinoid. Biologic medications may also be prescribed as these address the cause of psoriasis by targeting the immune system.
Biologics for psoriasis include:
- adalimumab (Humira)
- guselkumab (Tremfya)
- ixekizumab (Taltz)
- ustekinumab (Stelara)
Phototherapy is another treatment for psoriasis which involves controlled exposure to UV light. This method slows skin cell growth and reduces inflammation.
- Apply cool, wet compresses to the skin to reduce itchiness.
- Apply topical corticosteroid creams on itchy areas. Do not scratch them.
- Avoid extremely hot temperatures because sweat can worsen symptoms. Keep your skin clean, dry, and moisturized.
- Avoid using harsh soaps and highly fragranced products.
- Do not take long, hot baths or showers.
- Exposure to dust can contribute to eczema so having dust-protective covers on pillows and mattresses and dusting frequently can help.
- Take an antihistamine, such as diphenhydramine (Histergan).
- Take steps to reduce stress. Practice meditation, tai chi, or yoga.
If eczema is severe and does not respond to home treatments, medicated creams and ointments can reduce symptoms and their occurrence.
In addition to topical corticosteroid creams, your dermatologist may prescribe
calcineurin inhibitors (tacrolimus ointment and pimecrolimus cream). However, you should use these with caution as they carry warnings about a possible risk of cancer.
Some treatments can be used for either psoriasis or eczema, but depending on how severe your symptoms are, you might need a treatment that is specifically made for the skin condition you have.