A rash from poison ivy, poison oak or poison sumac is caused by an oil found in these plants, when this oil touches your skin it often causes an itchy blistering rash for many people the rash begins a few hours to a few days after skin has come in contact with the oil in some cases the reaction may not appear until one to two weeks later most people can safely treat the rash at home go to the emergency room if you have any of the following symptoms trouble breathing or swallowing or the rash covers most of your body, you may be able to treat your rash at home if the rash appears on a small section of your skin, you are absolutely certain that your rash is due to poison ivy, poison oak or poison sumac, if you are not certain, see a dermatologist and do not try to treat the rash at home if you’ve been exposed to poison ivy, poison oak or poison sumac. Rinse your skin right away with luke warm soapy water, you may be able to rinse off some of the oil, if not washed off, the oil can spread from person to person and to other areas of your body, thoroughly wash in a washing machine all of the clothes you were wearing when you came into contact with the poisonous plant, the oil can stick to clothing, if this oil touches your skin you can get another rash. Wash everything that may have the oil on its surface such as gardening tools, golf clubs leashes and even a pets fur, wash tools and other objects with warm soapy water. If you develop a rash from poison ivy oak or sumac, it usually lasts one to three weeks, during this time your skin can itch, it is best not to scratch, scratching can cause an infection, leave blisters alone. If blisters open do not remove the overlying skin as the skin can protect the raw wound underneath and prevent infection to ease the itch at home, dermatologists recommend trying one or more of the following, take short lukewarm baths with a product that has colloidal oatmeal which you can buy at your local drugstore. You can also draw a bath and add 1 cup of baking soda to the running water, short cool showers also can help, apply calamine lotion to skin, the itches, if you have a mild case a hydrocortisone cream or lotion may also help, you can make a cool compress by wetting a clean washcloth with cold water and wringing it out so that it does not drip, then apply the cool cloth to the itchy skin. Antihistamine pills can help reduce itching, use with caution as some antihistamines make people feel drowsy. Do not apply an antihistamine to your skin, some people develop allergic reactions to this medication causing more itching and rash.
If you have a serious reaction, you need to see a doctor right away especially if you have many rashes or blisters. You have swelling especially if an eyelid swells shut, the rash develops anywhere on your face or genitals or much of your skin itches or nothing seems to ease the itch, if your rash is not improving after 7 to 10 days or you think that your rash may be infected, see a board-certified dermatologist. A dermatologist can treat your rash and any infection as well as help relieve the itch.