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Plants like poison ivy, poison oak and poison sumac contain an oily resin called urushiol which is found in the leaves, flowers, stems, berries and roots of these plants. Urushiol can cause an itchy rash when people sensitive to the oil come into contact with it. This usually causes the skin to become red, sore and inflamed. This red rash usually present itself as lines or streaks of blisters or hives. About 50 % of people who come into contact with urushiol are sensitive to it hence, develop this itchy rash. When the plant is burned and the smoke is inhaled, it can be dangerous because it affects the lungs. Poison ivy rash usually does not require medical attention but in cases where the rash has spread to the face and genitals, your physician may prescribe corticosteroids like prednisone for a few weeks.


The oil resin (urushiol) in the leaves, flowers, berries, stems and roots of poison ivy, oak or sumac is an allergen that causes an allergic reaction (rash) when  people sensitive to it come into contact with it. This sticky oil can attach  to tools, clothing, animal fur or your skin when you come into contact with it. You can therefore get an allergic reaction when you directly touch the leaves, flowers, stems, berries and fruits of these plants because they contain the oil. Another way you can develop a poison ivy rash is when  you touch an object or animal fur  that has been contaminated with the oil and use your hand to touch your skin. If not cleaned, objects contaminated with urushiol can cause allergic reactions years later. Even the smoke from burning these plants contain the oil and can irritate the nasal passages and lungs. It is important to know that poison ivy rash itself is not contagious. The fluid in the fluid-filled blister  does not contain urushiol. The only way you can get it from someone is when you come into contact with the urushiol on a person’s clothes or him or herself.  Not everyone is allergic to this oil.


A family history for sensitivity to urushiol puts you at risk of this rash. There are also some outdoor occupation and hobbies that increase your risk. These include:


Construction workers



Fire fighters

Cable and telephone line installers




The common symptoms of poison ivy rash include the following:

  • red itchy skin
  • Swelling
  • Blisters

The rash looks like red streaks or lines because of the way the plant brushes against the skin. The rash may  however, be wide-spread if you come into contact with a contaminated clothing or animal fur. It may take 8 – 48 hours for the rash to appear although it can actually appear up to 15 days of contact. The rash may show up a week later after first time contact but subsequent contacts may show up as early as a day or 2. Poison ivy rash will then  take several days to develop on other areas that came into contact with the urushiol. The rash is not contagious and the fluid in the blisters are also not contagious. You can spread the oil to other parts of your body by touching them with your contaminated fingers or coming into contact with contaminated objects. The severity of the rash depends on the amount of exposure to the oil resin. Serious symptoms include swelling on the face, mouth, neck, eyelids and genitals. If left untreated, the rash may last from 10 days to  3 weeks or up to  6 weeks in very sensitive people.



There are no tests for a poison ivy rash. The doctor will just perform a physical examination of the rash and ask questions about any exposure to urushiol, outdoor hobbies and occupations. Most people do not need to even see a doctor when they develop the rash.



Poison ivy rash is usually treated successfully at home. First of all wash contact area immediately with soap, and use wet compresses  or take cools baths to relieve symptoms. Non-prescription antihistamines and calamine lotions may also relieve symptoms. In moderate to severe cases, your doctor will prescribe an oral corticosteroid (prednisone),  creams, ointment or shots for treatment. If a bacterial infection does occur at the site of the rash, an oral  antibiotic may be prescribed.



A bacterial infection of the blister or site of rash is the main concern here. An antibiotic will be prescribed for treatment in this case.



Here are a few tips to prevent the rash:

Avoid the plant.

Wash immediately after contact. This may prevent a reaction if the oil has not penetrated the skin

Use gloves or herbicides to remove or kill the plants

Clean all contaminated objects

Apply a barrier cream (IvyBlock) to the skin if there is a potentially exposure to these plants.









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