If all the oil can be washed off the skin within 5 minutes of contact, there should be no reaction. If the oil remains on the skin for more than 5 minutes, washing will not prevent the rash, but it will help to prevent spreading of the oil. Any clothing that might have come in contact with the oil also should be washed, before bringing it indoors, if possible. In addition, other items, such as garden tools and hunting or fishing gear, should be washed if they have been in contact with the plants. Thus, with the source of urushiol eliminated, a person with a mild rash requires little or no further treatment.
Calamine lotion is a good drying agent and helps to relieve the itching and inflammation.
Cool showers or soaking in a lukewarm bath with oatmeal or baking soda added will help dry blisters and provide comfort. A person should see a physician if the rash is severe, is on the face or genitals, or covers more than 20 percent of the body. The physician may prescribe medicines to reduce itching and inflammation. These may include antihistamines to be taken by mouth and corticosteroid lotions and creams to be applied to the skin. The doctor may prescribe oral corticosteroids in severe cases but also in some moderate ones.