Happy Trails Amid Poison Ivy

Feel like going camping or hiking this summer but are dreading that awful rash you got the last time? You don't have to live without the great outdoors if you learn what poisonous plants to avoid, CBS News Correspondent Dr. Emily Senay reports.

Touching poison ivy is enough to cause two-to-four weeks of miserable itching and scratching. The oils from the plant and its cousins, poison oak and sumac, can get onto skin and clothes, causing a strong allergic reaction.

The symptoms start with an itch and red rash that later develop into oozing blisters. But steps can be taken to avoid this.

Poison ivy is found throughout the U.S. and can be identified by its three-leaf clusters. The phrase "Leaves of three - let them be," may help hikers remember to walk around the ivy, which grows on the ground, in shrubs, or on long vines along trees.

Poison oak has a center leaf shaped like an oak tree leaf and tends to grow in small shrubs in eastern and western states.

Poison sumac is rarer, growing only in damp, swampy areas.

The best way to avoid contact with these poisonous plants is to stick to the trail paths found in parks. There is also an over-the-counter lotion available - Ivy Block - which claims to form a clay coating on skin that prevents plant oils from penetrating.

If you think you've touched one of these plants without protections, immediately wash your skin and clothing, as well as anything else they touched.

If a rash still develops, take aspirin or a bath with baking soda or oatmeal powder to soothe the itch. If you have a more serious rash, see a doctor, as some people need prescription steroids to clear up the reaction.

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