Poison ivy grows all over North America, and too many of us have no idea how to treat the painfully itchy rash it causes. This green, 3-petal leaf looks harmless enough and grows almost everywhere in the continent (except Hawaii and Alaska); most rashes occur after an unintentional brush with a plant in the backyard.

So, you have the telltale tingling in your arm, and it soon turns to a blotchy red rash.  The oil in the poison ivy causes the skin reaction, and it can get spread to others from your rash. What do you do? The first step is to wash your skin with warm and soapy water to try and remove the oil. Then, use a barrier cream from the drugstore, like IvyBlock, to prevent spreading. The rash will naturally fade in 1-3 weeks, but in the meantime, take cooling oatmeal baths to soothe the skin. Address the itchiness with over the counter calamine cream or aloe vera gel. Worst comes to worst, try an antihistamine that treats allergies.

Poison ivy affects most of us outdoorsy-folk at one point or another. It’s important to know what to do when it happens to you.