People who suffer from poison oak in fact have an allergic reaction to the stems or leaves of the western poison oak plant. This plant can grow up to six feet tall and it looks like a leafy shrub. In the areas which have a lot of shadow, this plant can grow as a climbing vine. The leaves of the poison oak usually have 3 separate leaflets but also they can be up to 9 leaflets and each leaflet is 1 – 4 inches long. In the spring the leaves of the poison oak can be green or red. This plant produces small green, yellow or white flowers. During the summer the leaves of the poison oak are green and this plant grows berries. In the late summer these leaves turn orange and red. This is a very uncomfortable rash. Like the poison sumac and poison ivy, this plant releases oil which is known as urushiol. This oil is released when it is damaged. When you touch this plant, then this allergen is absorbed by your skin. There are some studies in which is shown that only about 15 – 20 percent of people are not allergic to poison oak . If you want to prevent the poison oak rash, then you should avoid contact with it and you should know how to recognize it. You should know that the oil is contagious. You get this allergic reaction where you get in a direct contact with the poison oak or when you touch some objects or your clothes which came in contact with this plant. The poison oak rash is not contagious. In the blister fluid there is not oil and you will not spread this rash to other parts of your body or to another person when you touch him. You should avoid scratching and touching the poison oak rash. Also you should know that this rash does not spread from person to person. If you have a burning poison oak, then you should seek immediate medical help because it can disperse the oils in the smoke which can lead to lung irritation and severe respiratory problems.
People who are allergic to poison oak can see the signs of it from one to six days after they have been exposed to it. Most people are noticing these signs in the first 24 to 48 hours.  The skin rash which is also known as dermatitis is the most obvious evidence that you have an allergic reaction. You will notice some minor, itching and stinging irritation. Eventually, this irritation will break in a red rash which will be itchier as it is progressing. In the areas where you had a direct contact with this plant you will notice that the rash will be worse. You will notice that bumps will start to form and in some cases they can turn in large blisters which will ooze liquid. In a period of few days you will notice that these blisters started to dry up and they will form a crust. The poison oak rash is most likely to appear on the places where your skin is thinner such as neck, ankles and wrists. After a week that you have been in contact with this plant, the rash will peak and this rash can last from five to twelve days in the most cases. There are some rare cases in which this rash lasts for one month or more.  You need to recognize the poison oak rash and then you should wash your skin and clothes as soon as possible because it can linger on tools, clothing and other objects. You need to wash these objects with warm and soapy water.
A life – threatening allergic reaction: If you are allergic to something, then every time that you are exposed to poison oak plant this reaction has potential to become stronger. Here are the signs that you have severe allergic reaction:
- Swollen lymph nodes
- Nausea 
- Signs of infection such as pus or yellow fluid leaking from blisters or blisters that have an odor
- Rash that covers more than 25% of your body 
- Rash on your face, lips, eyes or genitals
- Eye or facial swelling
- Trouble swallowing
- Difficulty breathing 
These signs and symptoms can be life – threatening which means that you need to take immediate medical attention. Talk with your doctor as soon as possible. There are many medications and natural remedies that can help you to rid of this condition but you should not risk on your own without talking with your doctor.
Above are some of the symptoms of Poison oak.
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