What Is the Difference Between Eczema and Psoriasis?

Eczema and psoriasis are two types of skin rashes. Eczema is triggered by allergies and psoriasis occurs because your body is reacting abnormally.

Many people around the world have aggravating and uncomfortable skin conditions. Two of the most common of these rashes are eczema and psoriasis. 

It's essential to understand the symptoms and causes of each of the conditions so that you can talk to your doctor about them when they are diagnosing them. 

Both of these skin conditions can look the same. Eczema and psoriasis are different in that they can mean other things about your body or your environment. 

One is triggered by allergies and skin reactions. The other triggers because your body is reacting abnormally.

What is eczema?

Roughly 30% of all people are affected by eczema. Eczema is a skin condition that affects mostly adolescents and children. 

It can affect adults as well. It is often triggered by an allergic reaction to something you came into contact with. The skin reacts by turning red, swelling, and itching.

What is psoriasis?

Around 7 million people have psoriasis. Psoriasis appears on your skin in the same way that eczema does. The difference between psoriasis and eczema is that psoriasis is triggered by things that are not allergies. 

Psoriasis starts beneath the skin. It then grows into patches of thick and red itchy skin that shed scaly dead skin cells.

Eczema symptoms

There are several types of eczema: 

• Atopic eczema: This type of eczema tends to run in families with allergies and can come and go. 
• Contact dermatitis: This eczema is triggered by skin allergies after you touch something you’re allergic to.
• Nummular eczema: This shows up as small patches of red, irritated skin about a coin's size, typically showing up in adults. 
• Hand eczema: If you have eczema on your hands, it is commonly called hand eczema.
• Asteatotic eczema: This condition dries your skin out and makes it crack. It is usually found in older people and colder climates. 
• Stasis dermatitis: This eczema typically forms on your legs and calves and tends to happen to people with poor circulation in their legs.
• Lichen simplex chronicus: This eczema is self-induced. If you scratch an area too much, you can irritate the skin and cause it to thicken and turn red. 
• Seborrheic dermatitis: This is an oily type of eczema and is referred to as cradle cap.

Psoriasis symptoms

Plaque psoriasis is the most common form of the rash. In this type, patches form on both sides of your body. Guttate psoriasis forms as little, itchy scaly spots on the skin that form in groups. 

There are two kinds of rare psoriasis that are life-threatening. Erythrodermic psoriasis is a dangerous inflammation of the skin's entire surface. Pustular psoriasis is psoriasis with white pus pockets.

Doctors aren’t entirely sure what causes eczema and psoriasis. However, they have linked them to conditions and circumstances that can influence an outbreak. 

Causes of eczema

Eczema is believed to be triggered by allergic reactions to organisms or substances you encounter. The condition might also be passed down through inherited genes. Studies have shown that children whose parents have allergies and asthma are more at risk of developing eczema. 

Some other eczema triggers are believed to be:

• Cold or dry air
• Contact with chemical irritants
• Stress
• Skin lotions and soaps with fragrances
• The flu or a cold
• Pollen, pet dander, or foods

Causes of psoriasis

Psoriasis is known to be triggered by a disorder of your immune system. This is sometimes called an autoimmune disorder. The white blood cells in your body release an excess amount of chemicals used to fight illnesses. For some reason, this can cause your skin cells to rapidly age and flake off. 

Some of the known triggers for psoriasis are:

• Stress
• Sunburn or other burn injuries
• Some types of medications
• Heavy drinking and alcoholism
• Using tobacco products
• Cold and dry weather

Only a licensed healthcare professional can diagnose eczema or psoriasis. Questions and symptoms can be similar for both types of conditions.

Diagnosing eczema or psoriasis

Diagnosing either of these conditions involves a nearly identical exam at your doctor’s office. 

When you see your doctor, they will ask you about your family medical history to see if any skin conditions run in the family. The doctor will ask whether you work around chemicals or have recently come into contact with any. 

They’ll also ask about your alcohol and tobacco consumption and whether there seem to be certain times of year or weather conditions that seem to trigger it.

Your doctor will perform a physical examination of the areas that are affected. If they feel it is necessary, they might take a biopsy and send it to a lab for further analysis.

Treatment for eczema

Doctors usually treat eczema with a corticosteroid ointment or cream. If your eczema is stubborn and doesn’t go away, they might prescribe you some immunosuppressants and steroids. 

Antihistamines are used for contact dermatitis.

Treatment for psoriasis

Psoriasis needs to be treated differently than eczema. Doctors might prescribe ointments designed specifically for psoriasis that include vitamin D, calcipotriene, calcitriol, or vitamin A as a topical therapy.

If your psoriasis is severe enough, doctors can prescribe phototherapy, which involves using ultraviolet (UV) light in controlled doses. 

Extremely severe psoriasis is treated with acitretin, methotrexate, or cyclosporine. These are powerful biologic medicines that require careful dosage and oversight by a physician.