Psoriasis is a skin condition that causes discolored, scaly skin patches. It can occur anywhere on the body, but it’s often found around the knees and elbows.

You can develop psoriasis at any age, but the average age of people who develop it is 15–35 years old. It’s rare for children under the age of 10 years old to have the condition.

Psoriasis isn’t contagious, and it can appear in different forms. One of these forms is pustular psoriasis, which produces white, noninfectious pus-filled blisters (pustules). It’s very rare, affecting only 3.3 percent of people with psoriasis, according to an older 2009 survey. The survey used data collected between 1970 and 2000.

Pustular psoriasis can happen in conjunction with other forms of psoriasis, like plaque psoriasis. It can break out in single areas, like the hands and feet, or all over the body. It’s rarely seen on the face.

It usually begins with an area of skin becoming tender and discolored. Within a few hours, the telltale large blisters of noninfectious pus form. Eventually, these blisters turn brown and crusty. After they peel off, skin can appear shiny or scaly.

pustular psoriasis on the palms of the handsShare on Pinterest
Pustular psoriasis is a rare form of psoriasis that presents as pustules on the skin. It occurs in flare-ups and can be found on the hands. Mediscan/Alamy Stock Photo
pustular psoriasis on the sole of the footShare on Pinterest
People with pustular psoriasis can also have classic psoriasis, but not always. Stress, infection, or medication can trigger flare-ups of pustular psoriasis. Another common location of pustular psoriasis is the feet. puha dorin/Shutterstock
pustular psoriasis on the upper chestShare on Pinterest
The pustules of pustular psoriasis appear as small circles and are tender to the touch. Pus can ooze out of the pustules and cause infection. Photography courtesy of Indian Dermatol Online/PubMed Central

Pustular psoriasis isn’t a typical skin rash. Visit a doctor if you notice unusual skin changes or if you have a rash, blister, or open sore that doesn’t improve or worsens.

To diagnose pustular psoriasis, a doctor may perform a complete blood count to check for signs of elevated inflammation and abnormalities in your white blood cells (WBCs). If you have pustular psoriasis, your blood test results may show a reduced amount of lymphocytes, a type of WBC.

Sometimes, doctors will remove and examine a sample of a pustule to diagnose the condition.

There are multiple types of pustular psoriasis.

von Zumbusch pustular psoriasis

von Zumbusch psoriasis, or acute generalized pustular psoriasis, is the most severe type of pustular psoriasis. It’s very rare.

It begins with painful areas of red skin. Pustules form within hours and dry up in 1 or 2 days.

von Zumbusch psoriasis can recur in cycles, returning every few days or weeks. It’s rare in children, but when it does occur the outcome is better than when it appears in adults. In children, the condition often improves without treatment.

Symptoms may include:

Immediate medical care is necessary for this condition. Over time, von Zumbusch psoriasis can cause weight loss and exhaustion.

Potential complications include hair and nail loss, secondary bacterial infection, and liver damage. If left untreated, it can lead to cardiorespiratory failure.

Palmoplantar pustulosis (PPP)

Palmoplantar pustulosis (PPP) is also called localized pustulosis. This type of pustular psoriasis forms on the:

  • palms of the hands (usually at the base of the thumb)
  • soles of the feet
  • sides of the heels

The pustules begin on top of red patches of skin and later turn brown, peel off, and form a crust.

As with von Zumbusch psoriasis, PPP can come and go in cycles, leaving the skin with a rough, cracked appearance. People who smoke have a higher incidence of PPP than nonsmokers.

Symptoms may include:

  • itching
  • pain
  • a burning sensation in your hands and feet
  • difficulty walking and performing tasks using your hands

Acropustulosis

Acropustulosis is a rare type of pustular psoriasis. It’s clearly identifiable by the painful skin lesions that form on the ends of fingers and toes. When the pustules burst, they leave bright red scaly patches that can ooze.

This type of psoriasis is usually the result of a skin infection or an injury to the skin. It can become severe enough to cause toenail deformities and physical changes to the bone and finger.

Acropustulosis is sometimes confused with hand, foot, and mouth disease (HFMD). Unlike HFMD, acropustulosis isn’t accompanied by a fever or sore throat.

Experts aren’t sure of the exact cause of psoriasis, but they know that the immune system plays a role.

A variety of things may trigger psoriasis or increase your risk of developing it. Pustular psoriasis triggers include:

Medications

Certain drugs may also trigger pustular psoriasis. These include topical medications and systemic medications like corticosteroids. Flare-ups usually start about 2 to 3 weeks after you begin using the drug.

Pustular psoriasis can also be triggered by rapid withdrawal from topical or systemic corticosteroids like prednisone (Rayos). Prednisone is used for treating some skin conditions but is generally not advised for psoriasis due to the flare-ups it may trigger.

But a 2021 study of 1,970 people with psoriasis found that, after 3 months on systemic corticosteroids, very few people with pustular psoriasis experienced severe flare-ups.

The following are some of the medications that may trigger pustular psoriasis:

  • some beta-blockers for treating heart problems, like propranolol (Inderal LA) and nadolol (Corgard)
  • nonsteroidal anti-inflammatory drugs (NSAIDs), including aspirin, ibuprofen (Advil, Motrin), and the prescription medications naproxen (Anaprox DS, Naprelan, Naprosyn) and indomethacin (Indocin)
  • lithium (Lithobid)
  • antimalarial drugs like hydroxychloroquine (Plaquenil) and chloroquine
  • anthralin (Drithocreme, Dritho-Scalp), a topical medication used to treat hair loss

Pustular psoriasis of pregnancy, also called impetigo herpetiformis, is a very rare variant. It can be life threatening for the mother and fetus if it’s not treated.

Pustular psoriasis of pregnancy most often appears early in the third trimester. It can reappear in future pregnancies, usually at an earlier stage.

Symptoms may include:

  • pus-filled bumps on the inner thighs and groin that join together and spread
  • pustules in the mouth and under the nails

Although the exact cause is unknown, some possible risk factors may be a family history of psoriasis or a gene mutation triggered by increasing levels of progesterone.

Your treatment will depend on the type of pustular psoriasis you have and how serious it is. Sometimes it takes several tries or a combination of treatments to find the most effective approach.

Your doctor will probably prescribe ointments first because they can soothe your skin and reduce inflammation.

UV light, both natural and artificial, is used to treat psoriasis. PUVA therapy is a combination of UV light and psoralen, an oral medication that makes your skin more sensitive to it. PUVA stands for psoralen plus ultraviolet A.

Your doctor may also prescribe medications like:

TNF-alpha blockers and interleukin-12/23 inhibitors belong to a group of powerful drugs known as biologics.

Common treatments for different types of pustular psoriasis are also described below.

von Zumbusch psoriasis

Treatment for von Zumbusch psoriasis may include antibiotics, rehydration, and creams.

If these don’t work, your doctor may prescribe an oral corticosteroid to relieve symptoms. Sudden withdrawal of oral corticosteroids can cause recurrence of von Zumbusch psoriasis.

You’ll have to slowly wean yourself off this medication with a doctor’s supervision. Talk with your doctor about the risks of oral corticosteroids to fully understand the effects.

Treatment for von Zumbusch psoriasis also requires measures to prevent dehydration and skin infection.

Palmoplantar pustulosis

To treat palmoplantar pustulosis (PPP), you may need a combination of different treatments, like a topical treatment, UV light therapy, or an immune system suppressant like methotrexate.

Acropustulosis

There’s little evidence of what effectively treats acropustulosis. This condition is very rare and likely requires a combination of ointments and medications.

Pustular psoriasis of pregnancy

This very rare type of pustular psoriasis is difficult to treat. Commonly prescribed pustular psoriasis medications like oral retinoids aren’t recommended during pregnancy because they may cause developmental issues for the fetus.

Instead, treatments like high-dose corticosteroids, cyclosporine, or infliximab may be prescribed. UV light therapy or antibiotics are also possible treatments.

You may find that natural treatment options are effective against psoriasis if they’re used along with traditional remedies.

  • Aloe vera cream containing 0.5 percent aloe may help reduce scaling and redness.
  • Acupuncture may help relieve pain, although there are no clinical studies regarding its ability to treat pustular psoriasis.
  • Capsaicin, the substance that makes chili peppers hot, is available in creams and ointments. It may reduce pain by blocking your nerve endings. It may also help reduce inflammation and redness, but more research is needed to determine its effectiveness.
  • Epsom salt added to your bath water may help remove scales and relieve itching.
  • Curcumin, a chemical found in turmeric, has anti-inflammatory properties that can alter your gene expression. This helps to reduce psoriasis flare-ups.

Be sure to talk with a healthcare professional before trying any of these remedies.

Eating a diet rich in anti-inflammatory foods may help prevent flare-ups and could reduce your possibility of developing related health conditions like psoriatic arthritis or heart disease.

Although there’s little research on diets that may specifically affect pustular psoriasis, the following foods and supplements are recommended for helping to prevent psoriasis flare-ups in general:

  • vegetables like broccoli, cauliflower, and leafy greens like kale and spinach
  • berries, cherries, grapes, and other dark fruits
  • fatty fish, including salmon, sardines, and trout
  • fish oil supplements (an older 1988 study found significant improvement in a participant with pustular psoriasis who took fish oil supplements)
  • vitamin B12, vitamin D, and selenium supplements

Try to avoid the following foods and beverages:

  • red meat
  • processed meats like bacon and sausage
  • eggs
  • foods and beverages that contain gluten, including wheat, pasta, and beer
  • nightshade plants including tomatoes, potatoes, and peppers
  • alcohol

The appearance of your skin may cause feelings of anxiety, but the outlook for pustular psoriasis is good if you receive treatment.

Treatment can improve and eventually clear the skin. Your outlook will depend on:

  • the type of pustular psoriasis you have
  • the frequency of your flare-ups
  • your reaction to treatment
  • your overall health

Children who don’t develop secondary infection have a good outlook. In older adults, especially those with von Zumbusch pustular psoriasis, aggressive treatment is necessary to prevent serious complications. Treatment will also help reduce your risk of a flare-up.

It’s important to take steps to avoid triggers. These steps include:

  • avoiding environmental factors
  • quitting smoking, if you smoke
  • limiting sun exposure
  • minimizing alcohol use
  • taking steps to reduce stress, like deep breathing exercises or getting enough sleep
  • exercising regularly

You may also want to find a counseling or support group. Support groups can provide advice or insights into treatments or new research. Talking to someone about how your condition makes you feel may help with any anxiety or stress.