Ng says, “so if it’s the first time your body has ever seen it, it’s going to take a while for the rash to appear.”Īdvertising Policy Just how contagious is poison ivy? “Your immune system has to develop an allergic reaction first,” Dr. But if it’s your first time being exposed to the plant, it can take up to two weeks for a rash to appear. If you’ve been exposed to urushiol in the past and are re-exposed again, your rash will appear in four to 96 hours (though 24 to 48 hours is most common).
“It can even be weeping and crusting,” Dr. Poison ivy rash (along with the rash from poison oak and poison sumac) brings on bumps, blotches and, typically, a linear streak of swelling and blisters.
POISON IVY MEDICINE HOW TO
Ng talks about how to treat your poison ivy rash at home and what to expect as it heals. “You’ll get this rash everywhere the resin touches - and then, if you get it on your hands and touch your face or other parts of your body, you’ll spread it.”ĭr. “When the plant is broken, the resin leaks out,” explains dermatologist Pamela Ng, MD. An estimated 50% to 75% of the population is allergic to urushiol, which is found in every part of the plant, including the fruit, leaves, stem, and root. Poison ivy strikes again - or maybe it’s poison oak or poison sumac, as all three plants contain the same oily, allergy-inducing sap called urushiol. We do not endorse non-Cleveland Clinic products or services. Advertising on our site helps support our mission. Cleveland Clinic is a non-profit academic medical center.