It often takes just a few minutes for Urushiol (yoo-ROO-shee-all) to react with your skin. That means, if you slide through a grove of poison oak one hour into a four-hour ride, you're probably going to face some consequences. But you can minimize those consequences if, as soon as you get home, you hit the showers and you hit ’em right.
Urushiol is a thick, stubborn grease. Not unlike bacon grease. And if you're prepared to clean up that stubborn, delicious bacon grease (which you always should be), you likely have some Dawn dish soap handy. Pair it with a shower sponge or washcloth because you'll need some friction to help fight the battle.
It's best not to jump into a hot shower with contaminated skin because your pores will open up, the oil will thin out, and you'll be itching by morning. Cold-ish water will make your skin less receptive to urushiol, so point the shower knob to blue and grit your teeth. It'll be over in a minute, which you can’t say about a bad case of poison oak.