Poison ivy dermatitis

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The poison ivy is a woody vine with 2-4 leaflets in groups of three. The middle leaf has a longer stem than the other two. It is important to note that poison ivy adheres to the trunks of trees and other upright surfaces with hair-like airborne rootlets that grow out of the stem. In case the climbing surface is not accessible, poison ivy will grow as a free standing plant. The leaves of the plant turn into shades of purple and red during fall.

Poison ivy dermatitis is triggered by an allergic reaction to the slick layer that covers the plants and this resinous layer is called urushiol. An individual does not have to come in direct contact with the roots, leaves or branches to develop a rash. An individual can develop a reaction after exposed to contaminated clothing.

No individual is born with sensitivity to poison ivy but if exposed, an individual can become sensitized at some point and stay allergic. Remember that sensitivity can change at any time. There is no way to desensitize those who are allergic to the plant. Animals are not affected by poison ivy but an individual can develop a rash after petting a cat or dog that has been exposed.

Poison ivy dermatitis
It is important to note that the rash itself is not considered infectious and the blisters filled with fluid will not spread the rash.


It is important to note that the rash itself is not considered infectious and the blisters filled with fluid will not spread the rash. Poison ivy dermatitis manifests as soon as 4 hours or even 10 days after exposure, depending on the sensitivity of the individual and degree of exposure.

Once the rash manifests, the sensitivity level of the individual will increase. The individual will start to react at the slight trace of urushiol on the skin. This causes the rash to appear as if it is spreading even after treatment has been started.

The rashes are usually self-limited and later clear up without any treatment. A mild case of poison ivy dermatitis will heal over time but in severe cases, it would require treatment to reduce the discomfort. If the individual initially develops a rash, it lasts longer than a repeat attack, often 3-4 weeks.


Cortisone-type preparations taken orally are highly effective in managing poison ivy dermatitis. These medications are safe as long as taken for a short period (2-3 weeks). In case the individual has peptic ulcer, diabetes or high blood pressure, cortisone should only be taken under close medical supervision.

The itching and blisters will improve with the application of moist compresses. You can prepare a batch of Burow’s solution by adding 1-2 “Dome-Boro” tablets in a pint of water. This should be applied to the blisters for 20 minutes 2-3 times daily. After the compress, apply the prescribed cream if any.

Once the swelling subsides, discontinue the compresses and apply the prescribed cream. If the cream is applied before the swelling and blisters subside, it is not effective. The individual can shower or bathe as usual, but avoid using hot water.

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