Have you noticed itchy, flaky skin or unusual discoloration on your legs? This could be a sign of psoriasis, an autoimmune disease where the body’s immune system mistakenly targets its own skin cells. While psoriasis can appear anywhere on the body, it often shows up on the knees as well.

If your legs are itching and your dermatologist diagnoses psoriasis, there are some things you should know. Once you understand the condition, you’ll be in a better place to find a treatment that manages it effectively and helps keep symptoms under control.

Symptoms of Psoriasis on the Legs

Symptoms of psoriasis on the legs are similar to those elsewhere on the body. The specific symptoms you have will depend on the type of psoriasis your doctor diagnoses you with. In general, psoriasis on the legs involves flaky patches of skin. These can become inflamed and scaly, and they often itch or burn badly.

Although most studies don’t focus on the location of psoriasis unless it’s out of the ordinary (like on the hands or feet), about 3 percent of people in the United States are living with some form of the skin condition. Because the knees are one place where psoriasis is commonly seen, it makes sense that many people will have it on their legs at some point in time.

Here’s what you should know about the different types of psoriasis that can affect your legs.

Plaque Psoriasis

Eighty percent of people with psoriasis have plaque psoriasis, making it the most common type. Raised patches, known as lesions, stand out from the rest of the skin. They are usually red or purple, depending on your skin tone, and often look scaly. On your legs, you’re most likely to see plaque psoriasis on your knees, though it can show up anywhere on your skin.

Inverse Psoriasis

Approximately one-quarter of people with psoriasis live with inverse psoriasis. It occurs where the skin on your body folds and is most likely to touch other skin. Depending on your skin tone, you’ll see red, purple, or darkened patches. These patches will itch and burn but won’t get scaly. On your legs, you’re most likely to see this at the top of the back of the thigh, under the fold of the buttocks, or possibly behind your knees.

Guttate Psoriasis

About 8 percent of people with psoriasis experience guttate psoriasis. It usually looks like round, inflamed spots of skin. Depending on your skin tone, these spots can be red, purple, or just darker than the rest of your skin. These are called papules, and the legs are one area where they commonly appear, though you may see them on other parts of the body, too.

Pustular Psoriasis

Three percent of people diagnosed with psoriasis have pustular psoriasis.

You’ll see small, pus-filled bubbles or blisters, called pustules, under your skin. Pustular psoriasis can appear anywhere on the body, so you may see it on your legs.

Erythrodermic Psoriasis

Only 2 percent of people with psoriasis have a diagnosis of erythrodermic psoriasis. In this type, you’ll see large areas of the skin become red or purple, and all of that skin may shed at once. You may also get dehydrated, have severe pain and/or itching, and experience changes to your body temperature and heart rate. Erythrodermic psoriasis can affect all or most of your body, including your legs.

How Do People Experience Psoriasis on the Legs?

Psoriasis on the legs can cause the familiar itching and burning sensations associated with the condition.

One MyPsoriasisTeam member explained it this way: “The backs of my calves are scratched to death. Then comes the burn, and they feel like they are on fire.”

If the scales on your legs grow thicker, it can cause them to change color. This happened to a MyPsoriasisTeam member who said, “My psoriasis is flaring up even worse. It is turning white by my ankles and on my calves.”

Sometimes, psoriasis on the legs can cause enough discomfort to disrupt sleep. “This psoriasis is all over me. Both knees hurt and the top of my thighs. I don’t sleep at night,” one team member said.

Psoriasis on the legs may affect your daily activities, like whether you can work an entire shift. One MyPsoriasisTeam member said, “I made it to work. But I must leave early. Both ankles/feet/lower calves are burning and aching at the same time. Sometimes, I am tired of struggling.”

Psoriasis can limit the physical positions you’re comfortable in. Another MyPsoriasisTeam member said, “I have a bad bout of it on the back of my thighs. It hurts to sit, and I can’t stand for long periods.” When your legs itch and burn, it can be hard to find a comfortable position.

Psoriasis on the legs can affect the way you feel about your appearance. As one MyPsoriasisTeam member put it, “I have it badly on my calves, so I always wear a long dress or pants.” Covering it up can make you feel better about it, and wearing the right fabrics might help your skin feel better.

What Causes Psoriasis on the Legs?

The precise cause of psoriasis is not currently known. Researchers believe that the immune system becomes overactive, which causes changes to your skin. For instance, plaque psoriasis causes the skin cells to multiply too quickly. This causes a buildup of skin cells, which appear as the plaques, scales, and flakes that you see. Researchers don’t yet have a way to determine where your psoriasis will occur, so there’s no way to know what causes it to show up on your legs specifically.

You are more likely to get psoriasis if other members of your family have the condition. Smoking and obesity are also risk factors, as is a history of taking certain medications. If you’ve been diagnosed with HIV or if you’ve had a recent streptococcal infection, you’re also more likely to develop psoriasis.

Treatment for Psoriasis on the Legs

There are many treatments available for psoriasis on the legs. Your dermatology team should be able to help you find a treatment or combination of treatments adjusted to your type of psoriasis, severity, presence of other diseases, body type, lifestyle, and needs. Treatment should be completely explained, especially about the way it's administered and possible side effects.

Topical Treatments

Topical treatments for psoriasis on the legs include gels, ointments, lotions, moisturizers, creams, and more. They can help you hydrate your skin and may contain ingredients like corticosteroids, coal tar, salicylic acid, or retinoids, which may also help treat your psoriasis. You’ll need a prescription for some of these, so talk to your doctor.

Phototherapy

Phototherapy, also called light therapy, involves exposing the areas of your legs affected by psoriasis to certain types of light. You usually have to do this several times a week for one month or more. There are several types of phototherapy, and your medical team will help you choose what’s best for you.

Immune System Treatment

Because psoriasis is an autoimmune condition, treatment often involves addressing the immune system directly. Your doctor might recommend medications like methotrexate (Trexall) or cyclosporine (Gengraf, Neoral, Sandimmune). In more specific cases, biologics may be prescribed. These are strong drugs, but they come with significant side effects and are typically administered under certain conditions.

Find Your Triggers

If your psoriasis shows up out of the blue, look for what might be triggering it. If you can avoid triggers, you may be able to avoid flares, too. Common triggers like the weather, shaving, stress, alcohol consumption, and more can cause psoriasis on your legs.

Getting Medical Help for Psoriasis on the Legs

If you have new or worsening psoriasis on your legs, talk to your doctor to get medical advice right away. Similarly, if your psoriasis on your legs is not improving with treatment, talk to a health care provider to come up with a new plan. Your efforts will feel worthwhile when your legs are healing and your psoriasis flare-up is over.

Talk With Others Who Understand

MyPsoriasisTeam is the social network for people with psoriasis and their loved ones. On MyPsoriasisTeam, more than 124,000 members come together to ask questions, give advice, and share their stories with others who understand life with psoriasis and psoriatic arthritis.

Are you living with psoriasis on your legs? What does it feel like? Share your experience in the comments below, or start a conversation by posting on your Activities page.