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Outsmarting Poison Ivy and Other Poisonous Plants

First comes the itching, then a red rash, and then blisters. These symptoms of poison ivy, poison oak, and poison sumac can emerge any time from a few hours to several days after exposure to the plant oil found in the sap of these poisonous plants. The culprit: the urushiol oil. Here are some tips to avoid it.

Recognizing Poison Ivy, Poison Oak, and Poison Sumac

Poison Plant Rashes Aren't Contagious

Poison ivy and other poison plant rashes can't be spread from person to person. But it is possible to pick up the rash from plant oil that may have stuck to clothing, pets, garden tools, and other items that have come in contact with these plants. The plant oil lingers (sometimes for years) on virtually any surface until it's washed off with water or rubbing alcohol.

The rash will occur only where the plant oil has touched the skin, so a person with poison ivy can't spread it on the body by scratching. It may seem like the rash is spreading if it appears over time instead of all at once. But this is either because the plant oil is absorbed at different rates on different parts of the body or because of repeated exposure to contaminated objects or plant oil trapped under the fingernails. Even if blisters break, the fluid in the blisters is not plant oil and cannot further spread the rash.

Tips for Prevention

Tips for Treatment

Don't scratch the blisters. Bacteria from under your fingernails can get into them and cause an infection. The rash, blisters, and itch normally disappear in several weeks without any treatment.

You can relieve the itch by:

See a doctor if:

Content current as of: February 16, 2021

Source: FDA

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