What Is Poison Ivy?
Poison ivy is mostly found east of the Rocky Mountains, where it grows as vines or shrubs. The leaves can have either smooth or notched edges and are usually clustered in groups of three. Exposure to poison ivy can cause allergic contact dermatitis.
There is a phrase, "leaves of three, let them be" that can serve as a helpful reminder to identify and avoid poison ivy and other related toxic plants. Poison ivy is often identified by three leaflets with flowering branches coming from a single stem. You may also spot characteristic black dots on the plant, which is oxidized urushiol (the oil that causes the reaction to poison ivy plants). Poison ivy also produces a green or off-white berry-like fruit in the fall. Poison ivy plants can look different based on the season, growth cycle, region, and climate.
What Are Symptoms of Poison Ivy?
Symptoms of poison ivy exposure include a red rash, which:
- Usually appears within 4 hours to 4 days after exposure to the plant
- Typically starts as small red bumps, and later develops blisters that can be different sizes
- May crust or ooze
- Itches intensely
- Can occur anywhere on the body that has come into contact with the oil from the plant
- Can be in any shape or pattern, but commonly seen in straight lines or streaks across the skin
- Skin areas can break out at different times, which can seem as if the rash is spreading, however, leakage of blister fluid does not spread the rash
- The rash is spread by exposure to the oil from the plant which may linger on hands, under fingernails, on clothing, shoes, and gardening tools
- Lasts about two to three weeks
What Causes Poison Ivy?
The rash caused by poison ivy is an allergic skin reaction to an oil in the plant called urushiol. This oil is found in all parts of the plant, including the leaves, stems, roots, sap, and fruit (berries).
Exposure to the oil occurs through:
- By toughing any part of the plant
- Touching something that has the urushiol on it, such as garden tools or clothing
- Touching pets or animals that have been exposed to the plant oil
- Inhaling smoke from burning the plants
How Is Poison Ivy Diagnosed?
Poison ivy rash is usually diagnosed by the appearance of the rash alone. No additional tests are needed.
What Is the Treatment for Poison Ivy?
Self-care at home is all that is needed to treat poison ivy rash. The rash usually goes away on its own without treatment within one to three weeks.
If you are exposed to poison ivy or the oil, wash thoroughly with soap and water as soon as possible to get rid of the oils fast. Remember to get under the fingernails as well. Rubbing alcohol may also be used to dissolve and remove the oils from the skin. Fast removal of the oil will help prevent poison ivy dermatitis. If the oil is able to be removed within 10 minutes, a rash is unlikely to develop.
Treatments that may be used to help relieve itching, soreness, and discomfort caused by poison ivy dermatitis include:
- Skin treatments
- Oatmeal baths
- Application of cool wet compresses
- Calamine lotion
- Astringents containing aluminum acetate (Burow's solution) and Domeboro may help to relieve the rash once the blisters begin leaking fluid
- Steroid creams
- Best if used during the first few days of symptoms
- Over-the-counter hydrocortisone creams do not usually help; stronger prescription steroid creams may be needed
- Steroid pills or injections
- For secondary skin infections caused by scratching
Antihistamines are not generally used because they do not relieve itching caused by poison ivy dermatitis, however, antihistamines that make you sleepy such as diphenhydramine (Benadryl) may help you sleep through the itch. Antihistamine creams or lotions, anesthetic creams containing benzocaine, or antibiotic creams containing neomycin or bacitracin are not recommended because they could make the rash worse.
What Are Complications of Poison Ivy?
Complications of poison ivy include:
- Severe allergic reactions
- Skin infections
How Do You Prevent Poison Ivy?
The most effective way to prevent poison ivy dermatitis is to avoid the plant, and to learn how to identify it by appearance.
To minimize the potential for contact with poison ivy plants:
- Wear protective clothing to protect the skin, including heavy-duty vinyl gloves, long sleeves, and long pants when in areas where poison ivy may be found.
- Remember the resin and oils from poison ivy can be carried on clothing, pets, objects. and under fingernails.
- Use creams and ointments that create a barrier between the skin and the urushiol oil may help, such as Ivy Block or Stokoguard. Reapply every 4 hours.
- Do not burn poison ivy plants. Burning can release the allergens into the air irritating the skin, and inhaling particles from burned poison ivy can cause poison ivy dermatitis.
- If you come into contact with poison ivy:
- Remove any contaminated clothing. Unwashed clothes can retain the oil and cause a rash in anyone who wears or handles them.
- If you have to bathe exposed pets, wear protective clothing.
- Gently wash (do not scrub or rub) the skin and under the fingernails with mild soap and water as soon as possible.
- If the oil is able to be removed within 10 minutes, a rash is unlikely to develop.