How to Treat and Prevent Poison Ivy, Oak, and Sumac

Poison ivy, poison oak, and poison sumac all have a chemical irritant called urushiol that's secreted from the leaves or stalks. Most of us are allergic and react to urushiol with itching and a rash.



Poison ivy photo

raksybH / Getty Images

When it comes to poison ivy or poison oak, prevention is really the best medicine. However, my gut tells me you probably didn't look this up to see how to avoid poison ivy as much as how to treat it, so let's start there.


Symptoms and Treatment

This photo contains content that some people may find graphic or disturbing.

poison ivy rash

Belinda Hankins Miller

The good news is: the rash and itching will go away without any treatment. The bad news is: it will probably take a couple of weeks for it to go away. Treatment of poison ivy, oak, and sumac are all about comfort. You want to relieve the itching and inflammation.

  • Call 911 if you have any trouble breathing. This is especially true if you inhale smoke from burning poison ivy.
  • Call the doctor if the rash is on or around your eyes, covers a large part of your body, or seems to be infected (fever, swelling or oozing).

Here are tips to relieve the itching and rash. Some of these work better than others, so it's really a personal choice, and maybe a little trial and error:

  • Cold compresses on the rash for 15-20 minutes, several times per day. Don't put ice directly on the skin or leave cold packs on for too long: you can get frostbite from a cold pack if you're not careful.
  • Use calamine lotion, topical antihistamine or hydrocortisone cream to reduce itching.
  • Taking oral antihistamines such as Benedryl (diphenhydramine) should help reduce itching.

Here are some home remedies and alternative medicine treatments that might help with the itching:

  • Baking soda and colloidal oatmeal are protectants that relieve minor skin irritation and itching.
  • Aloe vera applied directly to the rash. If you have a plant, cut it open and rub the slippery part right on the skin. You can also try topical products with aloe included.
  • Take a cool bath.

Prevention is the best treatment for poison ivy. Knowledge is power. The way to prevent poison ivy, oak or sumac is to know what you're looking for and how to avoid it.


Avoiding Exposure

Clockwise from top left: poison ivy, poison oak and poison sumac.

Sam Fraser-Smith, Ed Bierman, Rusty Clark

Poison ivy, poison oak, and poison sumac all produce the toxin urushiol. More than half the population is allergic to this stuff, which will cause itching and a blistering rash if it gets on the skin.

Poison Ivy and Poison Oak

Poison oak is found on the West Coast and in the southeastern U.S. Poison ivy is found pretty much everywhere except Hawaii, Alaska, and parts of the west coast. Both of these come in a few different varieties and can grow as shrubs or vines. They typically like sunshine.​

There is an old rhyme that helps identify these pesky plants: "Leaves of three, let it be!"

Look for the combination of three leaves shown in these pictures. Poison oak will sometimes have a reddish coloration, either on the edges of the leaf or throughout the whole thing. They might have little yellow or white berries.

Poison Sumac

Poison sumac grows in the swamps and wetlands of the northeastern, midwestern, and southeastern United States. and doesn't follow the "leaves of three" rule that helps identify poison ivy and poison oak. Each leaf contains clusters of 7-13 leaflets. Poison Sumac's color varies based on the season - it will be orange in the spring, green in the summer, and yellow or red in the fall. It may have yellow-greenish flowers and whitish-green fruits that hang in loose clusters. 

Poison sumac grows as a shrub or a small tree. This variety produces the most urushiol in all parts of the plant, not just the leaves. Harmless sumacs contain clusters of red berries.

Cover Up

Besides avoiding it completely (learn to recognize the version of poison ivy, oak or sumac that grows where you live), the best prevention is to cover your skin. It doesn't take much of the urushiol to cause itching and blisters; in fact, you only need to brush up against the plant to get a reaction.

By covering your skin, you lessen the risk of exposure. However, you must wash clothing after contact with the plant, or you run the risk of secondary exposure to the oil. It also doesn't take much urushiol to cause irritation, and it can be spread from clothing to skin (even clothing to furniture to the skin).

Dangerous Dogs

Pets don't usually get a reaction to urushiol because their fur protects the skin from contact. Your dog can transfer the oil onto you, however, so Fido will need a bath if he's been rummaging around in the poison ivy bush. After you bathe the dog, bathe yourself.

One more thing: you can't catch a poison ivy reaction. Once the oil is gone, the threat is gone. The reaction is an allergy to the oil. The irritation, itching, and rash are not contagious. Some folks say you have about 30 minutes to wash up after an exposure to avoid the reaction.

Frequently Asked Questions

  • What is the difference between poison ivy, poison oak, and poison sumac?

    Poison ivy has three spoon-shaped glossy leaves that are red in the spring, green in the summer, and yellow or orange in the fall. It is more common in the United States in Eastern and Midwestern states. 

    Poison oak has between three and seven leaves with deep edges around each leaf that are similar to oak tree leaves. It is most common in the Western U.S. and sometimes found in Eastern states, but rare in the Midwest. 

    Poison sumac has clusters of pointed leaves, with between seven and 13 leaves per stem. It typically grows in wooded, swampy areas and is more common in the Southeastern states. 

  • How do you stop the itching of poison ivy or poison oak?

    Rashes from poison ivy and poison oak can be extremely itchy. To stop the itch, try applying a cold compress of an ice pack wrapped in a towel for 15 to 20 minutes at a time. Calamine lotion, a topical antihistamine, hydrocortisone cream, or aloe vera gel may also help soothe the itch. Another thing you can try is a cool bath with baking soda or colloidal oatmeal. 

    If the reaction is severe and home remedies do not bring relief, call your doctor. A course of steroids, such as prednisone, may be needed for the rash to heal.

  • Can poison ivy spread from person to person?

    Yes and no. A rash from poison ivy is not contagious. You cannot get poison ivy from another person's rash. However, if your skin touches someone or something contaminated with urushiol—the oily irritant found in poison ivy—you can develop a rash if you are allergic.

  • Does everyone react to poison ivy, oak, and sumac?

    No. Most people who come in contact with poison ivy, oak, or sumac will have an allergic reaction to the urushiol found in the leaves. However, not everyone gets a rash from poison ivy and similar plants. About 15% of the population does not react to poison ivy or similar plants.

  • How long does it take for poison ivy to clear up?

    Most of the time, poison ivy heals on its own in two to three weeks. It typically takes about a week for the oozing blisters to dry up. Once that happens the itching becomes less intense and the rash starts to fade. More severe cases of poison ivy can last longer but usually clear up within a month. 

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Poisonous plants,

  2. American Academy of Dermatology Association. Poison ivy, oak, and sumac: how to treat the rash.

  3. U.S. Food and Drug Administration. Outsmarting poison ivy and other poisonous plants.

  4. Cleveland Clinic. Poison ivy, oak, & sumac. Updated December 20, 2018.

  5. Pet Poison Helpline. Poison ivy.

  6. Harvard Health Publishing. Is poison ivy contagious? Updated July 2018.

  7. Johns Hopkins Medicine. Allergens: Poison ivy/poison oak/poison sumac.

  8. American Academy of Family Physicians: Poison ivy.

By Rod Brouhard, EMT-P
Rod Brouhard is an emergency medical technician paramedic (EMT-P), journalist, educator, and advocate for emergency medical service providers and patients.