How to Identify & Treat Poison Oak

Poison oak can cause an allergic reaction that results in an itchy, red rash.

Hikers, gardeners and outdoor explorers know the dangers of making contact with poison oak, which is a cousin to poison ivy and poison sumac. All of these plants have the poisonous sap urushiol in their roots, stems, leaves and fruit. Urushiol is released when contact is made causing a bruise to the leaves. As poison oak leaves are very fragile and easily bruise, the release of urushiol, which causes the allergic reaction, occurs quite easily.

Things You'll Need

• Water
• Washcloth
• Bathtub
• 1/2 cup baking soda or dry oatmeal
• Calamine lotion
• Antihistamine

Instructions

Identifying Poison Oak

1. Poison oak is a plant whose leaves are lobed and have a three-leaf pattern resembling young oak leaves. The flowers are small and yellowish-green.

2. In the spring poison oak leaves may be red, though not always. They turn a glossy green in summer and bright red or brown in the autumn. The leaves have a velvet feel to the underside.

3. The stems are gray-brown and the bark is smooth and light brown. Poison oak can grow close to the ground, as large as a bush or climb like a vine.

Appearance of Poison Oak Rash

1. A poison oak rash, like those from poison ivy and poison sumac, is a red, uncomfortable, and itchy rash that appears in lines or streaks and is accompanied by fluid-filled blisters or bumps and large, raised areas or hives. The more urushiol you contact with, the greater your reaction will be.

2. The rash usually appears eight to 48 hours after contact. The rash will continue developing over several days in areas that had contact with the urushiol or those parts where the urushiol was spread by touch.

3. A poison oak rash is not contagious. Once the rash appears it cannot be spread or caught, even through the fluid from the blisters.

4. Normally the rash lasts about 10 to 21 days. In those very sensitive to urushiol the rash can take up to six weeks to heal.

Treating Poison Oak

1. Wash the area that has made contact with the plant immediately with water.

2. Apply cold compresses and take cool baths to mitigate the effects. Try adding 1/2 cup baking soda or oatmeal to your bath to relieve the itch.

3. Apply calamine lotion and take oral antihistamines as directed to relieve itching.

4. See a doctor, who in severe cases may prescribe corticosteroid pills, creams, ointments or shots.

References

• Web MD: Poison Ivy, Oak, or Sumac
• Emedicine Health: Poison Ivy, Oak and Sumac

Resources

• Poison Ivy, Oak and Sumac Inforamtion Center