| |
1. Where is poison
ivy, poison oak and poison sumac found?
Poison ivy, poison oak and poison sumac grow practically everywhere
in the United States, except Hawaii, Alaska and some desert areas
of Nevada. They are the most common causes of allergic reactions
in the United States.
2. What causes the poison
ivy rash?
Poison ivy rash is really an allergic contact dermatitis caused
by a substance called urushiol, found in the sap of poison ivy,
poison oak and poison sumac. Urushiol is a colorless or slightly
yellow oil that oozes from any cut, or crushed part of the plant,
including the stem and the leaves. You may develop a rash without
ever coming into contact with poison ivy, because the urushiol is
so easily spread. Sticky, and virtually invisible, it can be carried
on the fur of animals, on garden tools, or on any objects that have
come into contact with a crushed or broken plant. After exposure
to air, urushiol turns brownish-black, making it easier to spot.
Once it touches the skin, the urushiol begins to penetrate in a
matter of minutes. It can be neutralized to an inactive state by
water.
3. How does the poison
ivy rash develop?
In those who are sensitive, a reaction will appear in the form of
a line or streak of rash within 12 - 48 hours. Redness and swelling
will be followed by blisters and severe itching. In a few days,
the blisters become crusted and begin to scale. The rash will usually
take about ten days to heal, sometimes leaving small spots, especially
noticeable in dark skin. The rash can affect almost any part of
the body, especially areas where the skin is thin; the soles of
the feet and palms of the hands are thicker and less susceptible.
4. Who is sensitive
to poison ivy?
We are not born with sensitivity to poison ivy. It develops only
after several encounters with the plants, and sometimes over many
years. Studies have shown that approximately 85 percent of the population
will develop an allergic reaction if exposed to poison ivy. Although
they are not sure why, scientists believe that an individual's sensitivity
to poison ivy changes with time and tends to decline with age. The
first bout of poison ivy usually occurs in children between the
ages of 8 and 16, and can be quite severe. Investigators have found
that people who reach adulthood without becoming sensitized have
only a 50 percent chance of developing an allergy to poison ivy.
5. What do poison ivy,
poison oak and poison sumac look like?
The popular saying "leaves of three, let them be," is
a good rule of thumb, but it's only partially correct. Poison ivy
or poison oak will take on a different appearance depending on the
environment. The leaves may vary from groups of three, to groups
of five, seven, or even nine. The plants grow near streams and lakes,
and wherever there are warm, humid summers. Poison ivy grows as
a low shrub, vine or climbing vine. It has yellow-green flowers
and white berries. Poison oak is a low shrub or small tree with
clusters of yellow berries and the oak-like leaves. Poison sumac
grows to a tall, rangy shrub producing 7-13 smooth-edged leaves,
and cream-colored berries. In the spring and summer, there is plenty
of sap, the urushiol content is high, and the plants are easily
bruised. Poison oak is found in the West and Southwest, poison ivy
usually grows east of the Rockies, and poison sumac east of the
Mississippi River.
6. How do you prevent
development of the poison ivy rash?
The best way to avoid the misery of poison ivy is to be on the lookout
for the plant whenever you are out-of-doors. If you are going to
be in areas where you know poison ivy or oak is likely to grow,
wear long pants and long sleeves and whenever possible, gloves and
boots.
If you think you've had a brush with poison ivy, poison
oak or poison sumac, follow this simple procedure:
Wash all exposed areas with cold running water as
soon as you can reach a stream, lake or garden hose. If you can
do this within five minutes, the water will neutralize or deactivate
the urushiol in the plant's sap and keep it from spreading to other
parts of the body. Soap is not necessary, and it may even spread
the oil.
When you return home, wash all clothing outside,
with a garden hose, before bringing it into the house, where resin
could be transferred to rugs or to furniture. Handle the clothing
as little as possible until it is soaked. Since urushiol can remain
active for months, it's important to wash all camping, sporting,
fishing or hunting gear that may also be carrying the resin.
7. What is the treatment
for the poison ivy rash?
Over-the-counter preparations like calamine lotion will relieve
mild rashes. Soaking in a lukewarm bath with an oatmeal or baking
soda solution is often recommended to dry oozing blisters and offer
some comfort. Cool showers will help ease the itching. In severe
cases, prescription corticosteroid drugs can halt the reaction if
taken soon enough. If you know you've been exposed and have developed
severe reactions in the past, be sure to consult your dermatologist.
|
