Q: My kids love playing in the woods near our house, but I’m worried about poison ivy. How do I treat it if I find those tell-tale itchy bumps on their skin?
A: Reactions to poison ivy, and the other “poison plants,” such as poison oak and sumac, become common irritants as the summer starts and we’re outside more and more and working in lawns and gardens.
This skin reaction is an allergic response to urushiol, a chemical found in these and related plants. Over half of the population will have this reaction—but that also means there really are people who don’t have an exaggerated skin reaction to the plant chemical. A really important point is that some of the worst reactions occur when people burn the plants or leaves and the chemical gets all over people’s skin, including the face, and even inhaled.
After exposure to the chemical, people will usually notice the skin reaction between 4 hours and 2 weeks later. Generally the more people have been exposed, the sooner the reaction will come out. Some people who have never been exposed before might not develop a rash for 2-3 weeks after they touch the plant. This can make it really difficult to remember where or when the exposure happened, and sometimes people doubt it is from poison ivy. The amount of chemical exposure also can change how fast the rash appears. For this reason, sometimes the rash will start on the hands, then the next day come out on the arms, and then later on the face. Because of this effect, people often think it’s spreading, but in reality once the oil is washed off of the skin the reaction does not spread but just erupts at different times.
The good news is that mild cases will go away on their own over time, and for worse cases there is very effective treatment! Most poison ivy reactions can be quickly calmed down and treated with a medium or high potency steroid cream put on your skin. Your doctor can prescribe that medicine for you. Cases involving the face or eyes or that cover much of the body often are treated with oral steroid medications like prednisone. A relatively low dose of medication can be used, but it should be prescribed for at least two weeks to decrease the risk that the rash flares back up after treatment. Otherwise, usual washing of the area with soap and water and avoiding scratching the area will help it resolve without complications.
Get outside, get in the yard, but leaves of three — let them be.
Got a question about your child’s health? Email Dr. Steiner or any of our local experts via firstname.lastname@example.org.
Dr. Mike Steiner is a pediatrician in the division of General Pediatrics and Adolescent Medicine at UNC and North Carolina Children’s Hospital.