When you have poison ivy rash, then this condition is caused by an allergic reaction to urushiol which is an oily resin. This oil is in the roots, stems and leaves of poison sumac, poison oak and poison ivy. If you come into contact with the urushiol, then you should wash your skin as soon as possible. If you know that you are not sensitive to this oil, then you can have a contact with it. If you wash this oil from your skin, then this can reduce your chances of getting poison ivy rash. People who get this kind of rush are having it in a period of few weeks and also this rash is very itchy. If you have mild case of poison ivy rash, then you can treat it at home with cool baths and soothing lotions. If your rash is widespread or severe, then you may need prescribed medications from your doctor. This is very important for your health if you have poison ivy rash on your genitals or on your face.
Here are the signs and symptoms of poison ivy rash:
- Difficulty breathing, if you have inhaled the smoke from burning poison ivy 
- Blisters 
- Swelling 
- Redness 
When you have poison ivy rash, then this rash looks like a straight line because this is the way in which the plant is brushing against your skin. This rash can spread more if you come in a contact with a pet fur or piece of cloth which are having urushiol oil on them. Also you can transfer this kind of oil to the other parts of your body when you are using your fingers. In the most cases this rash develops from 12 to 48 hours after you have been exposed to this oil.  When you get this condition, then it lasts from 2 – 3 weeks. How severe these rashes would be it depends from the amount of urushiol which is on your skin. People who have more urushiol oil on their skin will develop poison ivy rush more quickly. Your skin needs to come in direct contact with the urushiol otherwise you will not get poison ivy rash. This rash will not be spread if you have blister fluid. If you have noticed that this reaction is widespread or severe, then you should visit your doctor. If you have inhaled the smoke from burning poison ivy and you have noticed that you have difficulty with your breathing, then you must talk with your doctor as soon as possible.
Causes: When urushiol touches your skin, then it causes poison ivy rash. This oil is found in the roots, stems and leaves of poison sumac, poison oak and poison ivy. This kind of oil is very sticky which means that it can easily attach to your equipment, tools, clothing, skin and the fur of your pet. You can get this kind of rash from
- Inhaling smoke from the burning plants: The smoke from poison sumac, poison oak and poison ivy are having urushiol. This kind of oil can harm or irritate your lungs or nasal passages. 
- Touching contaminated objects: If you are walking through poison ivy and if you have touched your shoes this herb, then you may can get this oil on your hands which means that you can transfer to your body and face with rubbing or touching. If the object which has got poison ivy is not clean, then this can cause you poison ivy rash even they have passed many years. [2,3]
- Direct touch: If you have touched the roots, berries, leaves and steam of this plant, then you can get poison ivy rash.
When you have poison ivy rash, then you should know that is not contagious which means that it will not spread the rash because it does not have urushiol.
Risk factors: If you have exposure to poison sumac, poison ivy and poison oak, then these outdoor activities can lead to poison ivy rash:
- Cable or telephone line installation
- Fishing from the shoreline or hunting
- Camping 
- Construction 
- Firefighting 
Complications: If you have bacteria under your fingernails and you scratch a poison ivy, then this can make your skin infected. If you have noticed that the pus is oozing from your blisters, then you must immediately talk with your doctor. In most cases the best treatment for this poison ivy are prescribed by your doctor.
Above are some of the symptoms of Poison ivy.
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 U.S. Food & Drug Administration. Outsmarting poison ivy and other poisonous plants. Retrieved from www.fda.gov/consumers/consumer-updates/outsmarting-poison-ivy-and-other-poisonous-plants
 Nursing. Poison ivy. 2014;44(6):47.
 von Adelung E. An experimental study of poison oak. Archives of Internal Medicine. 1913;XI(2):148-64. doi:10.1001/archinte.1913.00060260029002
 Gladman AC. Toxicodendron dermatitis: Poison ivy, oak, and sumac. Wilderness & Environmental Medicine. 2006;17(2):120-8.