Psoriasis and poison ivy both affect your skin, but these conditions are different. Psoriasis is a chronic autoimmune disorder. It’s not contagious. Poison ivy is an allergic reaction, and it can be contagious. Learn more about these two conditions.

What is poison ivy?

A poison ivy rash is an allergic reaction to urushiol. Urushiol is an oil present on the leaves, stems, and roots of the poison ivy plant. This oil is also present on poison sumac and poison oak plants. If you touch these plants, you may develop an itchy rash that lasts up to several weeks. Not everyone is sensitive to the oil. Some people can touch poison ivy without having a reaction.

What is psoriasis?

Psoriasis is a common skin condition. An autoimmune disorder causes it. This condition changes the life cycle of your skin cells. Instead of your cells growing and falling off in a monthly cycle, psoriasis causes your skin cells to develop too rapidly over days. This overproduction can cause cells to build up on the skin’s surface, and it can lead to the development of red rashes and whitish-silver plaques.

What are the symptoms of poison ivy?

If you’re sensitive to poison ivy, you may experience these symptoms:

What are the symptoms of psoriasis?

If you develop psoriasis, you may experience the following symptoms:
  • red patches of skin
  • whitish-silver plaques, also called scales
  • dry, cracked skin
  • cracked skin that bleeds
  • itching, pain, or soreness around plaques

Tips for identifying poison ivy

A poison ivy rash may appear in straight lines. This is the result of plants brushing across your skin. The rash may no longer have those lines if you transfer the urushiol to your clothing or your hands and then accidentally spread it across your body. Symptoms typically begin to develop within a few hours or days after you come in contact with the plant. The more urushiol you come in contact with, the faster the reaction will be.

Tips for identifying psoriasis

Psoriasis can develop in one small area, or it can be widespread. Psoriasis patches are most common on the following areas:
  • elbows
  • knees
  • hands
  • feet
  • ankles
It’s less common but not impossible for rashes and plaques to develop on your scalp, face, and genitals. Unlike poison ivy, which typically goes away permanently after a few weeks with or without treatment, psoriasis will likely return. That’s because psoriasis is a chronic condition. Psoriasis is not always present for every person who has it. You may experience periods of inactivity. When this happens, the symptoms of psoriasis are mild or seem to disappear. Symptoms may return in weeks or months, or it may take years for the plaques to reappear.

How is poison ivy treated?

If you know you came into contact with the plant, immediately wash your skin with warm, soapy water. You may be able to rinse off most of the oil. Washing will also help prevent you from spreading the oil to other items, your pets, or other people. Wash your clothing and any tools or utensils that also came in contact with the plant. If you develop a rash, you may be able to treat it on your own with over-the-counter (OTC) anti-itch lotions, soothing bath solutions, and antihistamine medicines. In some cases, the rash may be too large or widespread, or cause too many blisters for OTC treatments. In those cases, visit your dermatologist. They may prescribe an anti-itch ointment, or corticosteroid in pill or injection form. If you develop blisters on your rash that burst, you don’t have to worry about the rash spreading. The fluid inside those blisters doesn’t contain urushiol. You should avoid scratching because scratching may lead to infections.

How is psoriasis treated?

There’s no cure for psoriasis. Current treatments are designed to ease the symptoms caused by the condition and reduce the length of outbreaks. Learn about 10 ways to treat psoriasis at home. Treatments for psoriasis fall into three categories:

Topical ointments

Several types of creams and ointments are used to reduce itching, swelling, and burning. Most of these are available only by a prescription from your doctor.

Light therapy

Controlled exposure to ultraviolet lights and even sunlight may lessen the severity of your psoriasis outbreak. Don’t attempt to treat yourself with light therapy without first talking with your doctor. Too much exposure may make the condition worse.

Systemic treatments

For more severe or widespread cases of psoriasis, injected or oral medications may help. These medicines can only be used for a brief period, so your doctor may rotate their use with other treatments.

What are the risk factors for poison ivy?

Outdoor activity is the primary risk factor for developing this rash. If you work or play outside, your odds of touching poison ivy are higher. This is especially true if you work in wooded areas. These are a few precautions that you can take to avoid or limit contact with the plant:
  • Learn to recognize poison ivy so you can avoid it.
  • Eliminate the plant with weed killing sprays if it begins growing in your yard.
  • Wear protective clothing when you’re in wooded areas. This can help you reduce the chances of the plant brushing across your skin.
  • Immediately wash any clothing or tools you use while outdoors to avoid spreading oils.
If you suspect a pet came in contact with poison ivy, bathe them to remove the oils from their skin. This will also help reduce your chances of coming in contact with the oils.

What are the risk factors for psoriasis?

You may have an increased risk for psoriasis if:
  • you have a family history of psoriasis
  • you have chronic infections or a weakened immune system
  • you have chronic stress, which can weaken your immune system
  • you smoke or use tobacco
  • you’re overweight or obese

When you should see a doctor

You may have difficulty breathing if you’ve been around burning poison ivy and you’ve inhaled the smoke. Seek emergency treatment if breathing problems are severe. If you have a poison ivy rash, you should see your doctor if:
  • the rash is severe
  • the rash is widespread
  • the swelling doesn’t stop with treatment
  • the treatments aren’t helping
  • the rash affects your face, eyes, or genitals
  • you develop a fever over 100°F (37.8°C)
  • your blisters become infected
See your doctor if your rash isn’t responding to home treatments or if you have a history of psoriasis and you think it caused your rash. Your doctor can help you eliminate other potential causes for your rash, including poison ivy, and determine if you have psoriasis.