Pustular Psoriasis: What to Know

Medically Reviewed by Zilpah Sheikh, MD on July 28, 2024
Written by Kendall K. Morgan
8 min read

Pustular psoriasis is a skin disease. You'll see white bumps filled with pus near or inside red skin blotches. These are called pustules. They can hurt and be scaly, flaky, or itchy.

It's most likely to affect:

  • The palms of your hands
  • The soles of your feet
  • Your fingers and toes

Even though you see pus in your bumps, it's not an infection. You can't catch pustular psoriasis from someone else or give it to others.

Pustular psoriasis usually affects adults. It's more likely as you get older but can happen at any age. It's rare for kids to have it. But it can run in families.

You can get pustular psoriasis on its own or with another kind of psoriasis called plaque psoriasis. About 3% of people with psoriasis will get this type.

Symptoms of pustular psoriasis include:

  • White or yellow bumps filled with pus
  • Pain
  • Inflammation of the skin
  • Redness

 

There are multiple types of pustular psoriasis. They fall into two broad categories, generalized or localized, depending on whether it affects a large area or is more limited. The types are based on where the blister outbreaks are or how fast they popped up. Sometimes you could have a mix of different types at once. Pustular psoriasis types include:

Palmoplantar pustulosis (PPP)

Your blisters form on small areas of your body, usually your palms or the soles of your feet. These pus-filled spots can turn brown, peel off, or crust over. Your skin can crack, too. This type of psoriasis may come and go. You're more likely to get this form if you smoke.

Acrodermatitis continua of Hallopeau

You'll have small, very painful lesions pop up on your fingertips or toes. The pain can make it hard to use your fingers or toes. In rare cases, it can cause nail or even bone damage.

Annular or circinate pustular psoriasis

Your pustular psoriasis will have a ring shape. They'll be red and scaly with pus at the margins. This type is not as severe.

Impetigo herpetiformis

This type of pustular psoriasis happens during pregnancy and is associated with low calcium or an infection during pregnancy. You'll have pus-filled bumps the size of a pinhead in groups or rings around red skin patches. They can form crusty, yellow plaques as they try out. You may have them on your scalp or neck. This type usually isn't on your face, hands, or feet.

Generalized pustular psoriasis or von Zumbusch psoriasis

Red, painful, tender skin blotches show up over a wide area of your body, and pus-filled blisters pop up soon after. Your skin may be very itchy. You also might be very tired or have:

  • Fever
  • Chills
  • Dehydration
  • Nausea
  • Weak muscles
  • Headache
  • Joint pain
  • Fast pulse
  • Weight loss

This is a rare and serious disease. See your doctor right away if you have these symptoms. It may be related to genetic abnormalities. 

Is acute generalized exanthematous pustulosis (AGEP) a type of pustular psoriasis?

This used to be considered a type of pustular psoriasis, but doctors now recognize it as a different condition with a lot of similarities to pustular psoriasis. AGEP has pus-filled blisters with no infection. But they happen because of a skin reaction not from systemic inflammation.

Psoriasis is an autoimmune disease. Your immune system usually sends white blood cells to fight disease in your body. But in this case, they attack your healthy skin by mistake. It likely happens in people who are more susceptible when triggered by factors such as stopping steroids suddenly. Your body may react by producing lots of inflammatory chemicals (cytokines) that cause white blood cells to build up in your skin. At the same time, other skin cells release factors that may make the pustules form.

Pustular psoriasis and chronic plaque psoriasis both show high levels of interleukins, which control your immune and inflammatory responses. But there are some differences in which interleukins you'll have more of. A mutation (or change) in one of two specific genes (IL36RN or CARD14) may make you more likely to get pustular psoriasis.

It usually isn't clear why pustular psoriasis flares happen. But a few things can trigger it including:

  • Medications, including lithium, iodine, penicillin, and interferon-alpha
  • Suddenly stopping steroids
  • Staph or other skin infections
  • Something that irritates your skin, like a topical cream or harsh skin care product
  • Too much sunlight
  • Stress
  • Pregnancy
  • Infection
  • Hormones
  • Electrolyte imbalances
  • Low calcium in your blood (hypocalcemia)
  • Phototherapy
  • Vaccines such as BCG or H1N1

You'll see a dermatologist (a skin doctor) who will ask about your symptoms, your medical history, and any family history of psoriasis or other skin conditions.

Your doctor will look at all of your skin. They'll also check your mucous membranes and nails to look for other signs of psoriasis. They may need to take a small sample of your inflamed skin to look at under a microscope. That's called a biopsy.

If you have a severe flare, they may also test your blood for signs of high white blood cell counts; signs that your kidney and liver are working the way they should; and whether you have healthy levels of electrolytes, calcium, and phosphate.

Your doctor may order these tests:

  • Complete blood count (CBC)
  • Electrolyte panel to look for low calcium levels in your blood (hypocalcemia)
  • Liver panel
  • Pregnancy test
  • Punch biopsy
  • Skin cultures

They'll want to rule out other conditions including:

  • Acute generalized exanthematous pustulosis
  • Drug eruption reaction
  • Pemphigus vulgaris
  • Pemphigus foliaceous
  • Impetigo
  • Dermatitis herpetiformis
  • Infected eczema
  • Erythroderma
  • Acute cutaneous lupus
  • Dyshidrotic eczema
  • Disseminated herpes simplex virus
 


 

 

The goal of treatment is to ease your symptoms and control outbreaks. What you take may depend on your type of pustular psoriasis and its severity.

Small, local outbreak. Your doctor may try a topical steroid cream first to treat the sores. Coal tar or salicylic acid creams can help with scaly skin. Synthetic vitamin D can help soothe the inflammation. You'll slather on lotions, creams, or ointments to soothe and prevent cracked skin. Then, you'll slip on cotton gloves or socks to hold the moisture in. You might get relief from a cool compress on spots that bother you or from an oatmeal bath.

PPP and acropustulosis outbreaks can be stubborn. Your doctor may try ultraviolet light treatments on the inflamed skin. This is called phototherapy.

Oral drugs such as cyclosporine or methotrexate may help calm down your immune system. Acitretin (Soriatane) is another drug that can slow skin outbreaks. It's a retinoid or a synthetic form of vitamin A.

All these drugs can have serious side effects, so you may need to switch treatments from time to time.

If you smoke, try to quit. Smoking makes your psoriasis harder to treat. Try to do things to lower your stress levels, such as exercise, yoga, tai chi, or meditation. Some people feel better, although no studies have proven this.

Widespread outbreak. If you have generalized or von Zumbusch psoriasis, get medical care right away. You'll need fluids along with treatments to prevent infection, ease your fever, and calm inflamed, broken skin. While you're in the hospital, you need to rest, stay hydrated, and keep cool.

Your doctor may treat you with injections of spesolimab-sbzo (Spevigo), a new antibody that blocks signals within the immune system to stop the flare.

Your doctor may also try acitretin, cyclosporine, methotrexate, steroids, or biologics (drugs made from living cells) such as etanercept or infliximab to get your flare under control. Once your skin redness and pustule outbreaks have calmed down, you can also try PUVA, where you take a drug called psoralen and then beam ultraviolet light at the affected area of your skin. Apremilast (Otezla) is also sometimes used.

Sometimes, one treatment doesn't do the trick. You may need to combine them to feel better.

Psoriasis itself doesn’t cause scarring. But patches can be itchy, which may lead you to scratch them. The more you scratch, the more damage you do to your skin. The best way you can help prevent psoriasis scarring and discoloration is to keep your condition well controlled as best you can. If you're worried about scarring or noticing scars, ask your dermatologist for advice on how to limit it.

 

 

Pustular psoriasis can be isolating. Because it's hard to predict when it will happen, you may have more anxiety. Some things that can help empower you while making a flare less likely include:

  • Manage stress. It’s been shown to worsen psoriasis.
  • Use bug repellent and sunscreen to prevent injury to your skin.
  • Limit alcohol. It can make psoriasis medications less effective.
  • Don’t smoke, and avoid people who do.
  • Limit showers and baths to 10 minutes, make them lukewarm, and slather on a fragrance-free moisturizing ointment or cream immediately afterward.
  • Try not to cut yourself during shaving.

Taking the right medications can also get your pustular psoriasis under control.

If you're struggling with mental health or feeling isolated because of pustular psoriasis, ask your doctor for a referral to a mental health provider who specializes in chronic conditions. Reach out to friends and family and consider joining a support group.

Pustular psoriasis is grouped into different types based on where it is located and how big an area it covers. It's usually not clear why it happens, but multiple things may trigger it. You'll have treatment options, including topicals, phototherapy, oral medicine, or biologics, depending on the severity of your symptoms and other health conditions.

What does pustular psoriasis look like?

You'll have pus-filled blisters and redness even though there's no infection. It may cover a large area or show up only in certain parts of your body.

What is the common treatment for pustular psoriasis?

Ask your doctor what they recommend. You might try topicals first if it isn't too severe. But more severe pustular psoriasis may involve systemic treatments with oral medicines or biologics. Ask your doctor what treatment they recommend for you and why.

How do I get rid of pustular psoriasis?

There's no cure for pustular psoriasis, but treatments are available. You also can try to avoid your triggers if you know what they are.

Is there a home remedy for pustular psoriasis?

You may find some ideas online for home remedies. It's best when you have pustular psoriasis to see your doctor and make sure that's what it is. Ask for advice on the best way to treat it and any other steps you can take to help it go away or prevent it from happening again. It's always a good idea to let your doctor know before trying over-the-counter medicines, supplements, or other home remedies.

How to treat itchy pustules on foot

If you have itchy pustules on your foot, you should see your doctor to get a diagnosis. It could be pustular psoriasis, an infection, or another condition. The best way to treat it will depend on what your condition is and what's causing it.