Which nasty plants?  Poison Ivy, poison oak, and poison sumac are all in their summer glory, waiting to ambush you and make you miserable!  The best defense is to be able to identify them and stay away from them.  Since they are all three-leafed plants, a good general rule is, if you see leaves of three, leave them be!  I have poison ivy bordering two sides of my property, and it doesn't bother me too much since I know it's there.  However, the vines love to stretch out from the shrubbery and tree line into my yard making it easy to accidentally walk on.  Plus my dogs can get into it.  Once anything makes contact with the leaves, the oil is easily transferred to something else.  It's like some horrible contagion that is difficult to control.

If your skin comes in contact with oil from any of these three plants, wash the area as soon as possible.  The same goes with clothing.  Don't allow the oil to transfer to anything else or it can become a nightmare.

if you are unlucky enough to have a reaction to one of these plants, there are many over-the-counter medications that can help.  However, if too much of your body gets covered with itchy blisters, you may want to consider seeing the doc as quickly as possible before the itching drives you crazy!  Been there-done that, and I know how nightmarish it can be.  Best of luck to you and yours against these nasty plants.