The leaves may turn colors in the fall. It may develop clusters of green or white berries. Protective clothing should be warn. After any possible poison oak exposure, it's important to bathe or shower as soon as possible, and to wash all clothing and other objects that may have touched the plant in hot water. Plain calamine lotion can temporarily reduce the itching.
Antihistamines given by mouth are also quite effective in reducing itch.
These include over the counter medications such as Benadryl or Chlortrimeton as well as prescription drugs. Mild rashes can be treated with a cortisone cream or lotion as prescribed by your doctor. For more severe cases, an oral cortisone, usually Prednisone, is prescribed for several days. It's important to follow the directions exactly, because if the drug is stopped too soon, the rash may re-appear. If blisters and oozing are present, your physician may recommend may recommend moist compresses with Burrow's solution.