According to experts, Poison Oak Rash symptoms and treatment options

This is what to do if you go on a hike but come back with a rash that looks angry.

Your leg is itching after a long day spent outside, maybe working in your garden or hiking on a trail. You look down and see a streaky red rash starting to form across the back of your calf and come to the frustrating realization that you must have encountered a poisonous plant and are having an allergic reaction.

The three likeliest culprits for skin irritation or rashes from outside plants are poison oak, poison ivy, and sumac. According to the American Skin Association (ASA), poisonous plant reactions affect roughly 50 million Americans annually because 85% of the US population is allergic to the oil that comes from these plants’ sap.

Sometimes, however, it can be difficult to identify the exact plant responsible for a rash, especially if you haven’t seen what it was. Here are the symptoms and treatment options for poison oak rashes.

What is poison oak, and why can it cause a rash in people?

Poison oak grows as a low shrub in the eastern and southern US, but it can also grow in tall clumps or long vines in the Pacific Coast, according to the US Food & Drug Administration (FDA). The plant is known for its “fuzzy green leaves”, which can be found in three groups and yellow-white berries.

According to experts, Poison Oak Rash symptoms and treatment options
Poison Oak Image

The allergic reaction is usually triggered by the sap of a poison oak tree and poison sumac and poison ivy plants. Health is told by Debra Jaliman MD, a dermatologist who is also an assistant clinical professor at Mount Sinai’s Icahn School for Medicine.

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Health is told by Joshua Zeichner MD, an associate director of cosmetic dermatology and clinical research at Mount Sinai Hospital.

Urushiol, according to the ASA, is colourless and odourless. This means that it’s difficult to tell when you have come in contact with it. Sometimes, you will only know if a rash develops. You don’t need to be in direct contact with poison oak to get a rash. However, you can touch other people who have come into contact with it. Dr Jaliman says that if your pet comes in contact with poison oak or other urushiol-containing plants, it can spread the disease to you through their fur.

What are the symptoms of a poison oak rash?

Generally speaking, the main symptom that comes after exposure to a poison oak plant (or other similar plants) is a red rash within a few days of contact, according to the Centers for Disease Control and Prevention (CDC). Dr Zeichner says that the rash is usually seen in streaks as the leaves touch the skin. “But, if you touch areas that are exposed to the urushiol with your fingertips, it can spread to other parts of your body.”

According to experts, Poison Oak Rash symptoms and treatment options
Poison oak symptoms Image

There may be several stages to the rash. Dr Jaliman says that the rash may appear as red, itchy bumps on your skin. The rash will then become crusty and blistered. A poison oak rash can take up to two weeks to heal, provided there is no infection.

Most people will experience a mild, itchy rash. However, 10%-15% of the US population are extremely allergic to urushiol. According to the American Academy of Dermatology Association (AADA), if you have any of these symptoms, you are having a serious allergic reaction to poison oak and should seek immediate medical care:

  • Either difficulty swallowing or breathing
  • A rash around your eyes and mouth or your genitals
  • A facial swelling around the eyes and nose
  • Itching severe enough to prevent sleep or worsen over time
  • Rashes all over your body
  • A fever is a condition that causes you to feel sick.

How do you prevent and treat poison oak rash?

Dr Jaliman says that you should wash your skin with soap and water if you suspect you have been exposed to poison oak. This will prevent the oil from spreading to other areas of your body.

Dr Jaliman recommends cool compresses and a quick, lukewarm soak with colloidal oatmeal to reduce itching. Our experts recommend that you use topical ointments such as OTC cortisone cream and calamine lotion to reduce itching. Dr Jaliman says that Benadryl may reduce allergic reactions, and Dr Zeichner suggests Vaseline soothe and protect the skin.

Dr Stevenson says that oral steroids may be prescribed in severe allergic reactions. If the rash is severe, a dermatologist can prescribe medication or prescription-strength creams. Dr Jaliman says that you can take Prednisone, and it will eliminate the rash in a matter of days or weeks.


However, prevention should be your first-line defence against poison oak rashes. Learn how to recognize the plant and how to avoid it. Dr Zeichner advises that long sleeves and pants are a must if you plan to visit a woody area. Dr Jaliman also recommends ivy blocker products, like Ivy X, which “create a barrier on your skin, making it harder to get the rash.”

Dr Jaliman recommends washing any materials that have come in contact with these plants, including gloves and gardening tools, as well as clothes worn during outdoor encounters.

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