| Poison ivy itches because your confused immune system thinks your body is under attack. Consequently, killer T-cells in your blood stream release enzymes and toxins that lay waste to the surrounds. Fluid oozes from blood and lymphatic vessels, flows over skin, and kills cells—both good guys and those chemically bound to the sap’s active ingredient, urushiol. Your deadly T-cell liquid damages nerve cells and that makes you itch. |
