How do I treat poison ivy?

What the evidence says

If your child has touched poison ivy, the most important first step is washing the skin right away. Use soap and cool water, since hot water can open up skin pores and let more of the plant's oily sap, called urushiol, soak in. Wash under fingernails too, and clean any clothes, shoes or gear that touched the plant.

The rash usually shows up as red, itchy, swollen patches, sometimes with blisters. It is not contagious, so your child can still go to school or daycare, and touching the blister fluid will not spread it to others. Most rashes are mild and clear up on their own within one to three weeks.

To ease itching at home, try cool wet cloths or cool baths, and calamine lotion. A doctor may suggest an oral antihistamine to help with itching, especially at night. Hydrocortisone cream can also help, but in Canada it should not be used on children age two or younger unless a doctor says it's okay.

Call your doctor if the rash is very severe, covers a large area, or involves the face or genitals, since steroid cream or pills might be needed. Also call if you see signs of infection, like increasing redness, swelling, pain, or a milky discharge, or if your child develops a fever.

Get emergency help right away if your child has trouble breathing or swallowing, or if their face swells up. This can happen with very severe allergic reactions and needs urgent care.