Effective treatments for poison oak include calamine lotion, cold compresses and antihistamines, according to WebMD. Doctors may prescribe oral prednisone or another corticosteroid for severe cases of poison oak exposure.
Patients with skin exposed to poison oak, ivy or sumac should wash the area thoroughly within the first 10 minutes of exposure, according to WebMD. Cleaning clothing, tools and equipment that might have come into contact with the plant is also necessary, as patients can be re-exposed to the plant through secondary contact. Patients with known severe allergic responses to poison oak should carry medication with them at all times.