Symptoms of Poison Ivy include rashes, which are an itchy, red, and bumpy skin reaction. These rashes can appear in a line or as a cluster of bumps on the skin. They may also be accompanied by swelling and blisters. In some cases, the rash may spread to other parts of the body. Poison Ivy is caused by contact with the plant's oil, which can be transferred through direct contact or indirectly through clothing, tools, or pets.