In most patients, contact with poisonous plants such as poison ivy, poison oak, and poison sumac results in an allergic reaction. Patients can also develop a rash from touching objects contaminated with oil from these plants. If you believe you have come in contact with a poisonous plant, our dermatologists can help you identify and pursue the best treatment option. The dermatology associates at Gainesville Dermatology & Skin Surgery treats a wide range of skin conditions, including rashes from poison ivy, oak, and sumac.

Contact us today to schedule a consultation and to learn more about our available skin treatments.

What Is Poison Ivy?

Poison ivy is a common poisonous plant that causes itchy skin rashes. Along with poison ivy, poison oak and poison sumac are toxic plants that also induce rashes. These plants produce an oily sap called urushiol that causes an allergic reaction in the skin when touched. Patients who touch these poisonous plants or an object that has been in contact with these plants develop an itchy rash, which is a form of allergic contact dermatitis — a red, itchy rash caused by direct contact with a substance or an allergic reaction to it.

How Common Is A Poison Ivy Rash?

A poison ivy rash is common — approximately 90 percent of those who come into contact with poison ivy, poison sumac, or poison oak develop an allergic reaction. What’s more, you don’t have to be exposed to a significant amount of urushiol to develop a rash — it takes an amount smaller than a grain of salt to cause a reaction. Patients can develop a rash from the following.

  • Direct contact with plant leaves
  • Inadvertently touching urushiol and then other parts of the body
  • Inhaling smoke from a burnt poisonous plant
  • Coming into contact with urushiol left on an object

Who Might Get A Plant Rash?

Nearly every patient who touches poison ivy, poison oak, or poison sumac leaves gets a rash. The following patients are more likely to come in contact with these plants than others, but anyone can come into contact with them and, subsequently, develop a rash. 

  • Hikers
  • Campers
  • Gardeners
  • Farmers
  • Landscapers
  • Groundskeepers
  • Forestry Workers
  • Forest Firefighters
  • Roofers
  • House Painters

What Do Poisonous Plants Look Like?

Poison ivy, poison oak, and poison sumac are three of the most common types of poisonous plants found throughout the continental United States. Each type has a distinctive appearance. If you come into contact with these plants, contact our dermatology associates.

Poison Ivy

The poison ivy plant is found throughout the country, but it appears differently in each part of the U.S. In the East, Midwest, and South, poison ivy grows as a vine, while in the northern and western parts of the country, it grows as a shrub. Each poison ivy leaf has three leaflets. A wise rule to remember when identifying poison ivy is, “leaves of three, let them be.” The plant has bright-green leaves that turn red in the spring and yellow, orange, or red in the fall.

Poison Oak

The poison oak plant closely resembles poison ivy — both have leaves with three leaflets — but poison oak has rounded tips. Poison oak leaves have an underside that is fuzzy and much lighter in color than the top portion of the leaf. Poison oak grows as a shrub, and it is more commonly found in the western United States than in any other region. The shrub can have either white or yellow berries.

Poison Sumac

The poison sumac plant grows as a woody shrub with each stem containing pairs of 7–13 leaves. Poison sumac can be distinguished from non-poisonous sumac varieties by the appearance of its berries. Poison sumac has drooping clusters of green berries. Harmless sumac has red berry clusters that grow in an upright direction. Additionally, poison sumac is more common in wet, swampy areas, such as the southeastern part of the U.S.

Poison Ivy Rash Symptoms

The effect — an itchy, red rash — of exposure to urushiol oil is the same no matter what poisonous plant a person is exposed to. Depending on the degree of skin sensitivity, a patient may develop a rash within a few hours to a few days after initial contact with poison ivy, poison sumac, or poison oak leaves. These symptoms can likewise occur after a patient comes into contact with an object that has been exposed to these plants. A rash from a poisonous plant, however, is not contagious — you can’t get a poison ivy rash by touching another patient’s rash. Poison ivy, poison sumac, and poison oak symptoms include the following.

  • Red & Itchy Skin
  • Skin Rash 
  • Oozing Blisters
  • Red Bumps (Papules)
  • Redness
  • Swelling
  • Irritation

How Is A Poison Ivy Rash Diagnosed?

A Gainesville dermatologist on our team will examine the rash, assess the patient’s symptoms, and ask the patient questions to determine if they might have encountered a poisonous plant. There is a wide range of allergens and irritants besides poisonous plants that can likewise result in contact dermatitis or an itchy, red rash. If a patient has not been outdoors or in contact with any plants, our team will rule out other potential skin conditions or causes.

Poison Ivy, Oak & Sumac Rash Treatment

There is no cure for a rash from poisonous plants once the rash starts. Avoiding these plants is the best type of poison ivy treatment — it’s important to learn what the plants look like and to exercise caution if you are ever around them. Rashes from poison ivy, oak, and sumac typically dissipate within 1–2 weeks of development. During this period, over-the-counter creams — such as calamine lotion or a colloidal oatmeal bath — and prescriptions — including oral medication for severe itching and steroid cream or a steroid injection for swelling and itching — may be recommended by our team. Prescription drugs (such as prednisone) may be required to help calm severe reactions and in cases when the irritation includes mucus membranes (membranes found in the eyes, nose, mouth, and genitals). To learn more about poison ivy, poison oak, and poison sumac rash treatment options, contact Gainesville Dermatology & Skin Surgery.

How To Prevent A Poison Plant Rash

The best way to avoid developing a rash is to learn what poisonous plants look like so you can avoid coming into contact with them. If you believe you have come into contact with poison ivy, poison sumac, or poison oak, consider the following tips.

  • Apply rubbing alcohol to exposed body parts and contaminated items
  • Scrub your hands and under your fingernails to strip away the oil
  • Use dish soap and lukewarm water to wash hands
  • Wash all clothing after spending time outdoors
  • Wear protective clothing and gloves while outdoors
  • Wear rubber gloves when cleaning items exposed to poisonous plants