Poison Oak/Sumac

Poison Oak and Poison Sumac Symptoms, Treatment and Prevention

If you’ve ever had a poison oak or sumac rash, you know how itchy and uncomfortable an allergic reaction can be. These are two dangerous native plants that grow in the wild and can cause severe rashes on the skin when touched. Urushiol, the same oil that is found on the leaves and stems of poison ivy, is also responsible for your skin’s reaction to poison oak and poison sumac.

It’s a smart idea to educate yourself about what poison oak and sumac look like so that you can identify and avoid them. You should also become familiar with the safe and effective ways to treat these rashes in case you come into accidental contact with the plants.


Symptoms typically appear 24 to 72 hours after exposure to poison sumac and poison oak and include:

  • A red rash, often in a distinctly striped formation
  • Streaks or patches of red bumps, often with blisters
  • Skin inflammation, a burning sensation, and swelling

But at times, the rash does not appear until up to five days after exposure.Symptoms often occur in phases, starting with redness and then progressing to a rash and blisters.The rash may last for two to three weeks, and is typically at its peak during days four to seven.Poison oak symptoms can be mild or severe, but it’s important to not ignore them and seek treatment immediately to avoid a risk of further contamination or medical complications.

The rash may last for 2 to 3 weeks, and is typically at its peak during days 4 to 7.

Get Medical Help If:

  • You experience difficulty in breathing
  • The rash shows signs of infection
  • The rash covers most of your body
  • You experience swelling, especially around the eyes or in the throat
  • The rash develops on your face or genitals
  • You have had severe reactions to urushiol in the past
  • If condition worsens or symptoms persist for more than seven days

Poisonous plant rash is a common skin affliction, but it can result in serious complications for some individuals who come in contact with the plant. Everyone’s reaction to poison oak is different, and you might not know how it affects you until it’s happening for the first time.

Experienced healthcare professionals can often diagnose a poison oak rash just by looking at it. When you arrive at your physician’s office, you’ll likely be asked a few questions about the circumstances of your exposure, your symptoms, and your medical history. Except in rare cases, x-rays and lab tests are not needed for patients with poison oak rashes.

Is it contagious? No. Only direct contact with the plant’s oil will result in a rash. Fortunately, this rash is not contagious in the traditional sense, and it does not spread easily to other areas of skin or transfer to other people. You can only get a rash by touching the oil of the plant, not the fluid from existing blisters. If it seems like your rash is spreading, it is likely just a delayed reaction of your skin in an additional area that was directly exposed to the plant. Some areas of skin react quicker to the poison than others.

The exception here is if you still have urushiol oil on your skin and touch another person’s skin. In this instance, the other person’s skin can have a reaction as well. Although the rash itself is not contagious, urushiol can be passed from person to person and even to objects and animals. That’s why it is so important to thoroughly wash all affected areas and objects so that active urushiol is not passed on to someone else.


According to the American Academy of Dermatology, the rash you get from poisonous plants is caused by an oil called urushiol. Poison ivy, oak, and sumac are close relatives of each other and members of the same plant family.

You can contract a skin rash from both the leaves and the stems of these plants, and even dead plants still contain residual urushiol. Your skin may not be sensitive to urushiol right away but rather build up sensitivity after the skin has been exposed. Oftentimes, people have no reaction at all the first time they come into contact with poisonous plants. The human immune system works to prepare a defense for the next time that the skin encounters the poisonous substance, thereby sensitizing the skin and causing an allergic reaction.


The first step in treating a poison oak reaction is recognizing the rash and washing your skin and clothes as soon as possible. Urushiol can linger on clothing, tools, and other objects, so try to wash all affected materials with warm, soapy water within the first 30 minutes of exposure.

Domeboro® Soothing Soak helps to effectively soothe the uncomfortable symptoms of poison sumac or poison oak exposure, in a different way than ordinary creams and lotions. As an astringent solution, Domeboro® gently dries out rashes and reduces the redness and blisters on irritated skin. Doctor-recommended for the treatment of skin irritation caused by poison plants for over five decades, Domeboro® gently dries out rashes and reduces the redness and blisters of irritated skin, while calming the urge to scratch, which may result in additional complications such as infection.

Domeboro® can be used with a compress/wet dressing or as a soak. Mix one, two, or three packets in 16 ounces of cool or warm water.

  • Compress or wet dressing: Immerse a compress or wet dressing in the solution and apply to affected area for 15 to 30 minutes. Repeat as needed or as directed by a doctor.
  • Soak: Immerse the affected area directly in the solution for 15-30 minutes. Repeat the soak 3 times a day or as directed by a doctor. Discard the solution after each use.

Other Treatments for Poisonous Plants

As soon as possible, after contact with the plant or its oil, rinse skin thoroughly with Isopropyl (rubbing) alcohol or a grease-cutting soap (such as dishwashing liquid or liquid laundry detergent). You may wish to apply calamine lotion or an over-the-counter corticosteroid cream to temporarily lessen itching. Some doctors recommend taking over-the-counter oral antihistamines, such as diphenhydramine, to soothe itching and promote sleep.

Another way to soothe the symptoms of poison oakand sumac rashes is to take an oatmeal bath. You can pour a couple cups of oatmeal into a nylon stocking (tying it at the top) so that your warm bath water flows through the oatmeal and into your tub. Baking soda is another home remedy that is used to soothe the symptoms of poison oak at bath time. It’s a good idea to soak in the tub for about 30 minutes to let the soothing ingredients fully penetrate your skin. Some doctors also recommend over-the-counter remedies like calamine lotion and antihistamine pills to help relieve itchiness.

Although scratching or picking at a rash won’t cause it to spread, it will prevent it from healing properly. There is no urushiol present in the fluid of blisters, but that still doesn’t mean you should touch or pop them. Consider covering your rash with a loose bandage to prevent subconscious touching, and apply a poison oak treatment or poison sumac treatment as directed by the product manufacturer and your doctor.

Although poisonous plant rashes are serious conditions that requires treatment, the symptoms are temporary and will go away with time and proper care. For most people, the rash should go away within a few days or weeks. However, some people with very sensitive skin or a more intense allergy to urushiol can experience the symptoms of the rash for a month or longer.


It’s a smart idea to learn to identify the plants so that you can steer clear of them.

Poison oak is a plant that has the appearance of a green, leafy shrub and can grow to heights of up to six feet tall. You can often identify poison oak because the leaves tend to cluster in sets of three. The “rule of three” can be deceiving though because poison oak has also appeared with leaves in clusters of five, seven, and nine. These leaflets typically grow to lengths of one to four inches. Poison oak tends to grow in shaded forest areas and can be found in the form of shrubs or vines. It also thrives along roadsides, in uncultivated fields, and parcels of abandoned land.

The leaves of poison oak look somewhat like leaves of an oak tree, but with a glossy greenish color on top. The underneath sides of a poison oak plant are typically less shiny and look velvety in appearance. Underneath, the leaves are also usually much lighter in color and covered with tiny hairs. However, the leaves can be red, yellow, or brown in color depending the season and how healthy the plant is. Poison oak stems can be greyish in color and covered in small thorn-like parts. If you encounter the plant in the summer or fall, you may see light green or whitish berries growing on the stems.

Poison sumac grows on sparse shrubs and trees about five to 20 feet in height. It is often identified as a small plant with upward-pointing leaves with small branches that have red-colored stems. You should also look for double rows of leaves on the stems and oval or oblong-shaped leaves that taper to a point on each end.

Poison sumac leaves often have a smooth or wavy appearance. However, they change color throughout the year and may appear reddish in the fall and greenish in the spring and summer. Often inhabiting swamps and other wet areas, this plant is typically more allergenic than poison oak and poison ivy.

Here are a few quick reference points to remember:

  • Poison Oak: found mostly in the western U.S., grows like poison ivy (vine, shrub or individual plants). It has compound leaves with clusters of 3, 5, or 7 leaflets that have a resemblance to oak tree leaves. Look for light green, shiny leaves with hairy undersides.
  • Poison Sumac: found in swampy, wet areas in all of the southern states east of the Mississippi, poison sumac grows as a shrub, with each reddish (sometimes gray) stem containing 7 to 13 leaflets arranged in pairs with a terminal, larger leaflet. It usually has drooping clusters of green berries.

While attempting to identify a plant in the wild and determine if it is poison oak, never use your bare hands to examine it. Use a stick or a gloved hand instead to protect your skin. If it appears to be poison oak based upon the appearance, wash anything that came in contact with the plant with warm, soapy water as soon as possible. Make sure to scrub underneath your fingernails if you think you have come in contact with poison oak because urushiol can linger under your nails.

Wear long sleeves, long pants, and closed shoes when walking in areas where these plants may grow. Urushiol can remain active for at least 5 years on clothing, shoes, pet fur, and any surfaces that have come into contact with the oil. Wash contaminated clothing and shoes (including the laces) with soap and hot water. Bathe pets. All objects and surfaces that have come into contact with the plant, such as gardening tools and gloves, should be cleaned with a diluted bleach solution or swabbed with rubbing alcohol.

When you go hiking or camping, bring along a small bottle of dishwashing soap. Standard soap that you use to wash your dishes is also great for washing away the poisonous residue from these plants. Stash a few paper towels and some extra water in your hiking satchel for emergency situations as well.

If you live in a wooded area, carefully remove poison oak plants from your property to reduce your risk of developing a rash. Avoid burning wood or brush that is near poison oak plants as well. And finally, never let small children or pets play in wooded areas unattended. They could be exposed to the poisonous plants without realizing it and bring the urushiol back to the house on their clothing, hair, or fur.

If you are looking for poison sumac/poison oak treatment products, learn more about Domeboro® astringent solution in powder form.

Domeboro*** February 21, 2019