Poison ivy, oak and sumac contain an oil called urushiol (you-ROO-shee-all). In most people, this oil causes an allergic reaction when it comes into contact with the skin, resulting in an itchy rash.
Poison ivy reaction
WHAT KIND OF CONTACT WITH THESE PLANTS CAN CAUSE AN ALLERGIC REACTION?
Every part of poison ivy, oak and sumac plants — the leaves, the stems and even the roots — contains urushiol, so you can experience an allergic reaction after any contact with them. Anything with this oil on it can cause an allergic reaction, so you also may experience a rash after touching something else — like a gardening tool, sporting equipment or even a pet’s fur — that has been in contact with these plants.
Additionally, poison ivy, oak and sumac release urushiol into the air if the plants are burned. If airborne oil particles land on your skin, you can experience an allergic reaction.
The first time you come into contact with urushiol, you may not experience a reaction for up to 21 days. If you have had an allergic skin reaction to urushiol in the past, the rash will likely appear sooner, within 12 to 72 hours.
Poison ivy, oak and sumac rashes are not contagious. It is not possible to get this type of rash by touching someone else’s rash.
WHAT ARE THE SIGNS AND SYMPTOMS OF AN ALLERGIC REACTION TO POISON IVY, OAK OR SUMAC?
An allergic reaction to the urushiol found in these plants can cause:
- Intensely itchy
- Redness or red
- Black marks, if the oil dries on the
The rash can appear on any part of your body. It may take longer to appear on some parts of your body than others, due to a delayed reaction in these areas.
If you are exposed to airborne urushiol particles, you may develop an allergic reaction and experience:
- Swelling and redness, especially on the
- Swollen eyelids.
- Black marks on the skin from dried
Whether you touch a plant or get airborne particles of oil on your skin, the rash usually lasts 10 to 21 days.
WHAT SHOULD I DO IF I COME INTO CONTACT WITH THESE PLANTS?
- Rinse your skin with generous amounts of lukewarm water, which will inactivate the oil and remove it from
your skin. This is most effective when done within 15 minutes of exposure.
- If you shower, make sure you rinse your skin thoroughly with lukewarm water before using soap. Urushiol can stick to soap. If this happens, the soap can spread the oil all over your
- Wash all of the clothes you were wearing. Washing will remove any urushiol that remains on the clothing. Touching unwashed clothing that has the oil on it can result in an allergic
- Wash everything that you had with you when you came into contact with the plant. Urushiol can stick to the surface of items like gardening tools, pet leashes and bicycles for a long time, and touching these items can result in an allergic
Typical case of poison ivy
HOW CAN I TREAT MY RASH?
Your skin will be itchy while it is healing. You can relieve the itching by:
- Taking short lukewarm baths in a colloidal oatmeal preparation, which you can buy at your local
- Applying calamine
- Taking cool
- Applying cool
- Taking an oral Do not apply a topical antihistamine to your skin, as this could make the rash and itchiness worse.
- Applying hydrocortisone cream or lotion to mild
DO I NEED TO SEE A DOCTOR?
If the previous recommendations are not enough to control your symptoms, you should visit your doctor. You may need a prescription topical steroid ointment or a strong oral (taken by mouth) medication such as prednisone.
If the rash covers most of your body or you have trouble breathing or swallowing, you should visit the emergency room.
A board-certified dermatologist can help if you’re not sure whether your rash was caused by contact with poison ivy,
oak or sumac, or something else. The dermatologist can provide an accurate diagnosis, which will result in the best outcome.
HOW CAN I RECOGNIZE POISON IVY, OAK AND SUMAC SO I CAN AVOID TOUCHING THEM?
HOW CAN I PROTECT MY SKIN?
If it is not possible to avoid going into areas where poison ivy, oak and sumac grow, you can protect your skin by applying a skin care product called an ivy block barrier. This type of product contains an ingredient called bentoquatum, which helps prevent urushiol from penetrating the skin.
Dermatologists also recommend wearing long pants, long sleeves, boots and work gloves made from a heavy fabric. These add another layer of protection to your skin.
A board-certified dermatologist is a medical doctor who specializes in the diagnosis and medical, surgical and cosmetic treatment of skin, hair and nail conditions. To learn more about poison ivy, oak and sumac or find a dermatologist in your area, visit aad.org/poison-plants or call toll-free (888) 462-DERM (3376).
All content solely developed by the American Academy of Dermatology.
Copyright © by the American Academy of Dermatology and the American Academy of Dermatology Association.
Images used with permission of the American Academy of Dermatology National Library of Dermatologic Teaching Slides
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