Imagine having painful blisters on your hands or fingers that just won’t go away. This is the case with two skin conditions — herpetic whitlow and dyshidrotic eczema. At first glance, they may seem quite similar, but here’s the catch: They have distinct treatments, making it crucial to pinpoint which condition you’re experiencing. After all, getting the right diagnosis is the first step toward effective treatment and relief.

Continue reading to learn more about the similarities and differences between herpetic whitlow and dyshidrotic eczema. This article covers how common these conditions are, what causes them, symptoms, how they’re diagnosed, treatments, and more.

How Common Are These Conditions?

Dyshidrotic eczema is more common than herpetic whitlow. Dyshidrotic eczema causes between 5 percent and 20 percent of all cases of hand dermatitis (irritated, inflamed skin on the hands). By comparison, only about 2 people per 100,000 are diagnosed with herpetic whitlow in the United States.

What Causes Herpetic Whitlow or Dyshidrotic Eczema?

Even though herpetic whitlow and dyshidrotic eczema share similar symptoms, they are caused by very different things. Their causes and the way they’re treated can be quite different.

Herpetic Whitlow Causes

Herpetic whitlow is caused by the herpes simplex virus — the same virus responsible for cold sores or genital herpes. If the virus infects the skin on your fingers or hands, it can cause an infection there, resulting in a blistering rash. It’s most common in people who come into contact with saliva or other body fluids that may be infected with the herpes virus, such as:

• Children who suck their thumbs
• Health care professionals, such as dental hygienists or respiratory therapists
• People who are exposed to genital herpes
• Athletes in close contact with each other, such as wrestlers

You may be more likely to have an eruption (outbreak) of herpetic whitlow if you have a weakened immune system caused by a medical condition or medication.

Dyshidrotic Eczema Causes

Dyshidrotic eczema is a type of eczema that causes symptoms on your hands, fingers, or feet. It’s also known as dyshidrosis, acute palmoplantar eczema, vesiculobullous dermatitis, or pompholyx.

Although the cause of dyshidrotic eczema is unknown, it’s most common in certain groups of people, including:

• People 20 to 40 years old
• Females
• People with a family history of eczema
• People with a family history of contact dermatitis (a rash caused by contact with an allergen or irritant)
• People getting immunoglobulin infusions to treat a weak immune system

About half of dyshidrotic eczema flare-ups are caused by contact with a trigger, such as:

• Metals like cobalt or nickel
• Laundry detergent
• Frequently wet hands caused by sweat or hand-washing

A MyEczemaTeam member talked about another trigger of their dyshidrotic eczema: “Anyone with dyshidrotic eczema notice that heat/sweat triggers it? Especially for the soles of the feet?” Hot, humid weather and sweating can also trigger a dyshidrotic eczema flare. As with other types of eczema, stress and allergies to food or seasonal pollen can also trigger dyshidrotic eczema.

When you come in contact with a trigger, your immune system overreacts, resulting in inflammation that causes many of the symptoms of dyshidrotic eczema.

What Are the Symptoms?

Herpetic whitlow and dyshidrotic eczema have several symptoms in common.

Both conditions cause painful blisters to form on the hands or fingers. The main difference in the symptoms is the location of the blisters.

Herpetic Whitlow Symptoms

If you have herpetic whitlow, the blisters usually form close to your fingernail. Usually, you only have symptoms on one finger. However, the symptoms can spread to other fingers.

Before you notice any blisters forming, you may feel pain or tingling in the area. Shortly after the initial pain and tingling, blisters or fluid-filled bumps may start to appear close to a fingernail. The skin around the affected area may become sensitive to the touch. You may also notice that the affected finger is swollen and discolored — usually a darker color than the surrounding skin.

The blisters usually start to heal in a few days, with a crust forming where the blisters once were. The symptoms usually last about two weeks. However, they may last longer if you don’t treat them.

Dyshidrotic Eczema Symptoms

If you have dyshidrotic eczema, blisters — also called vesicles — form on the skin of your palms, sides of your fingers, or soles of your feet. The blisters are usually small (about 1 to 2 millimeters across), but they might merge to form larger blisters. Most of the time, you’ll have a rash on both sides of your body — on both hands or feet. As the rash develops, it may feel itchy and painful. A MyEczemaTeam member with dyshidrotic eczema described the blisters as “aggravating and itchy.”

Similarly to herpetic whitlow, you may notice itching and burning sensations in the area first. “I feel a tingly itching/burning sensation where I’m going to get eruptions,” shared a MyEczemaTeam member.

The itchy blisters caused by dyshidrotic eczema usually start to go away in three to four weeks. However, you may have some scaling (dry, flaky skin) in the area after the blisters heal.

If you have dyshidrotic eczema, your symptoms may come and go. A MyEczemaTeam member who had dyshidrotic eczema when they were in high school commented, “I used to scratch the blisters, and after they would pop, they would go away only to return later.”

Are These Conditions Contagious?

Herpetic whitlow is contagious — the infection can spread to another person through physical contact. It’s most contagious when there are blisters on your skin, and the virus can spread from the blister fluid. Once the blisters start to form a crust, they usually aren’t contagious anymore. If you have herpetic whitlow, you may want to cover the blisters to avoid spreading it to others.

Dyshidrotic eczema is not contagious. Just like other types of eczema, you can’t spread dyshidrotic eczema to other people, even when you have blisters on your skin. However, if you break your skin by scratching, the wound can become infected.

How Are These Conditions Diagnosed?

A dermatologist usually diagnoses herpetic whitlow or dyshidrotic eczema based on its appearance and history. Your doctor may ask questions to find out if you have had contact with possible triggers or saliva infected by the herpes virus.

To confirm your diagnosis or rule out other possible causes, you may have additional tests, such as:

• Biopsy — A procedure to remove a sample of skin to run further tests
• Allergy testing — A test to identify what substances you’re allergic to
• Blood tests — Tests to measure substances in your blood to help find a diagnosis
• Culture test — A test to find out if the herpes simplex virus is causing an infection

It’s possible to have both conditions at the same time. In fact, a different type of eczema — called eczema herpeticum — can occur when a large area is infected by the herpes virus.

How Are These Conditions Treated?

The medications used to treat herpetic whitlow and dyshidrotic eczema aim to address the cause of the rash. By targeting the underlying causes, these treatments not only ease the symptoms but also help prevent future flare-ups and improve overall well-being.

Herpetic Whitlow Treatment

If you have herpetic whitlow, your doctor may prescribe antiviral medication to fight the viral infection. Antiviral medications can be taken by mouth or applied to the skin. An example of an antiviral medication is acyclovir (Zovirax) or valacyclovir (Valtrex). If you’re in pain, your doctor may also recommend an over-the-counter pain reliever, such as ibuprofen (Motrin) or acetaminophen (Tylenol).

Talk to your doctor about the best way to care for the rash to prevent infection. Keeping it covered may help protect the wound and prevent you from spreading the infection to others.

Dyshidrotic Eczema Treatment

If you have dyshidrotic eczema, your treatment will be tailored to your symptoms. Many of the treatment options will focus on decreasing inflammation, such as:

• Topical corticosteroids — Ointments or creams that decrease inflammation in the area they’re applied, such as hydrocortisone (Cortizone-10) or triamcinolone (Kenalog)
• Oral corticosteroids — Steroid medications that decrease inflammation all over your body, such as prednisone (Deltasone)
• Immunomodulating drugs — Medications that reduce inflammation by altering (adjust or regulate) your immune system, such as methotrexate (Trexall), mycophenolate mofetil (CellCept), or dupilumab (Dupixent)

Your doctor may recommend other remedies to help with the pain and itching associated with dyshidrotic eczema, including:

• Taking antihistamines — Medications that can help improve itching, such as cetirizine (Zyrtec) or fexofenadine (Allegra)
• Soaking the affected area in cool water or applying cool compresses
• Frequently applying moisturizers

To sum it up, herpetic whitlow and dyshidrotic eczema may seem similar, but they’re actually two different conditions. Herpetic whitlow is caused by a virus (herpes simplex) and is contagious. Dyshidrotic eczema isn’t contagious and usually has more to do with allergies and skin sensitivity. It’s essential to understand the differences to get the right treatment. If you think you might have either condition, don’t wait — see a doctor as soon as you can and take the first steps toward feeling better.

Talk With Others Who Understand

MyEczemaTeam is the social network for people with eczema and their loved ones. On MyEczemaTeam, more than 49,000 members come together to ask questions, give advice, and share their stories with others who understand life with eczema.

Have you had blisters on your hands, fingers, or feet? Have you been diagnosed with herpetic whitlow or dyshidrotic eczema? Share your experience in the comments below, or start a conversation by posting on your Activities page.