By Janis Graham
If you've been exposed to poison ivy, liquid dish soap could spare you from the red, itchy rash. When researchers swabbed the forearms of medical students with crushed poison-ivy leaves, then rubbed a patch with everyday dish detergent for 25 seconds before rinsing, they found that dish soap prevented a reaction in almost half the volunteers and reduced the inflammation and blistering in the rest by 56 percent. The soap works because it strips your skin of the plant oil that's responsible for causing the rash. But for it to work you need to wash within two hours of exposure, before the oil has time to bind to your skin cells, says Dr. Stibich, a coauthor of the study. He adds that any full-strength dish detergent will do the trick.