Poison Ivy, Sumac, and Oak

What is poison ivy, sumac, or oak?

“Poisoning” from plants such as poison ivy, poison sumac, and poison oak is an allergic reaction that happens when your skin touches these plants. Contact with the oil in these plants causes most people to have a rash, blisters, and itching. This contact usually happens in the spring and summer.

Poison ivy and poison oak have three leaflets on each stem and grow as a vine or bush. Poison sumac has opposing rows of 7 to 13 leaflets on each stem, with one leaflet at the end of the stem. It grows as a shrub or tree usually in damp, cool, marshy places. The poisonous oil is in the sap of these plants and oozes from any cut or crushed part of the plant, including the roots, stems, and leaves.

How does the allergic reaction occur?

The allergic reaction happens after touching one of these plants. A reaction can also occur after contact with anything that carries the oil from the plants, including clothes, tools, animal fur, or ashes and smoke from burning plants.

What are the symptoms?

The symptoms of an allergic reaction to poison ivy, sumac, or oak include the following, from least serious to most serious:

  • itching, often intense  

  • red blotches that may be raised or flat  

  • blisters, which may show up in rows where the plant or sap touched you  

  • fever  

  • headache  

  • swelling of your throat and eyes  

  • overall swelling of your body  

  • stomach cramps, nausea, vomiting, diarrhea  

  • sudden wheezing from breathing burning poison ivy (this can become a severe asthma attack).  

Usually the rash is first noticed 1 to 2 days after contact. How bad the rash will be depends on:

  • the thickness of your skin  

  • how allergic you are to the plant  

  • how much of the plant’s oil you were exposed to  

  • how soon you were able to wash off the plant’s oil.  

How is it diagnosed?

Your Reddy Urgent Care healthcare provider will ask about where you have been recently and will examine the rash. The rash is usually a line or a cluster. It is usually red and raised and often has little blisters. If the oil was rubbed or wiped on the face, there may be swelling of the eyelids. The diagnosis is usually a combination of the appearance of the rash and the history of being in the woods, yards, or flower garden, where the plants are likely to grow. You can also get exposed by holding a pet that has just run through a patch of the plants.

How is it treated?

To treat contact with poison ivy, sumac, or oak, follow these steps:

  • As soon as possible, wash all exposed skin gently with strong soap and water (or just water) to remove the plant’s oils. A new product called Zanfel is a strong soap that is especially effective in preventing or relieving poison ivy symptoms.  

  • Remove your clothes and shoes. Wash your clothes in detergent and water.  

  • Soak some cloth in aluminum acetate solution (Burrow’s solution) and put the cloth on the rash. Then put calamine lotion or ointment on your skin to reduce the redness, ease the itching, and help dry up the blisters. Soaking in a lukewarm bath with cornstarch (1/2 cup) or colloidal oatmeal added may help ease the itching. DO NOT put lotion containing antihistamine on your skin.  

  • Cover any oozing blisters with a clean gauze bandage soaked in a baking soda and water solution.  

Once the oil is washed off the skin, the rash cannot be spread by scratching itchy skin or from oozing blisters. However, scratching may lead to infection of the open sores.

Taking an oral antihistamine, such as Benadryl, can help with the itching but will not clear up the rash.

If you have severe coughing or wheezing, especially with throat swelling, from burning poison ivy, oak, or sumac, you need medical treatment right away.

If the rash spreads to your face, mouth, eyes, or genitals, or if you have a fever, headache, extreme redness, pus, or other severe symptoms, see your Reddy Urgent Care healthcare provider. He or she may recommend one or more of the following:

  • Putting a steroid ointment or cream on the affected areas according to the directions on the package.  

  • Taking oral corticosteroids such as prednisone.  

  • Taking oral antibiotics or using an antibiotic cream if the rash becomes infected.  

Because these are all potent drugs, ask your healthcare provider about any possible side effects or interactions with other drugs you may be taking. For example, using a steroid for a long time can have serious side effects. Take steroid medicine exactly as your healthcare provider prescribes. Don’t take more or less of it than prescribed by your provider and don’t take it longer than prescribed. Don’t stop taking a steroid without your provider’s approval. You may have to lower your dosage slowly before stopping it.

How long will the effects last?

The rash usually takes 1 to 3 weeks to heal.

How can I take care of myself?

Follow the steps outlined above to treat your rash. In addition, keep the affected skin clean and dry. Keep your fingernails well trimmed and clean. Try not to scratch your skin. Scratching could cause an infection. Scratching and infection can cause scarring.

See your healthcare provider if you develop severe symptoms. See your provider right away or get emergency care if your throat starts to swell or if you have asthma, your wheezing is getting worse, and your regular medicines aren’t helping.

What can I do to help prevent a reaction to poison ivy, sumac, or oak?

  • Know what the plants look like and where they grow so you can avoid them.  

  • Wear long-sleeved shirts and long pants if you are going to be in an area where these plants grow.  

  • You may want to use IvyBlock skin cream, which is specifically made to block poison ivy.  

  • As soon as possible, preferably within 5 to 10 minutes of contact with one of these plants, rinse exposed skin thoroughly with soap and water (or just water). Be sure to clean under your fingernails.  

  • Wash clothes in hot water and detergent to remove any oil that may be on them. Also clean shoes, tools, camping or fishing gear, or anything else that has been in contact with the plants. Wear gloves when you do the washing and cleaning and then throw the gloves away.  

  • Give any outdoor pets a bath if you think they have had contact with the plants. Wear gloves and avoid contact with their fur while bathing