If you’ve ever brushed up against poison ivy and noticed an itchy rash developing soon after, you’re not alone. Poison ivy is one of the most common causes of allergic skin reactions in the U.S. While the rash itself is unpleasant, many people are surprised, and even alarmed, when it begins to blister. So, is it normal for poison ivy to cause blisters? In short, yes. Blistering is a common and natural ...