Poison
Sumac

THIS ARTICLE IS MEANT TO BE A REFERENCE ONLY SEE YOUR
DOCTOR IMMEDIATELY IF YOU SEE SYMPTOMS.
Poison
sumac is found in wooded swampy areas. Few people are likely to
come in contact with it. It is a tall shrub or small tree with
6-12 leaflets arranged in pairs, and an additional single leaflet
at the end of the midrib. The small yellowish green flowers, borne
in clusters, mature into whitish green fruits that hang in loose
clusters 10-30 cm in length. The male and female flowers of poison
sumac are on separate plants, as in poison ivy and western poison
oak. Although nonpoisonous sumac species have leaves similar to
those of poison sumac, the nonpoisonous species have red fruits
that form distinctive, erect, cone-shaped terminal heads, not the
hanging whitish green fruits of poison sumac.
Approximately
85 percent of the population will develop an allergic reaction if
exposed to poison ivy, oak or sumac, according to the
American
Academy
of Dermatology. Nearly one-third of forestry workers and
firefighters who battle forest fires in
California
,
Oregon
and
Washington
develop rashes or lung irritations from contact with poison oak,
which is the most common of the three in those states.
Usually,
people develop a sensitivity to poison ivy, oak or sumac only
after several encounters with the plants, sometimes over many
years. However, sensitivity may occur after only one exposure.
The
cause of the rash, blisters, and infamous itch is urushiol
(pronounced oo-roo-shee-ohl), a chemical in the sap of
poison ivy, oak and sumac plants. Because urushiol is inside the
plant, brushing against an intact plant will not cause a reaction.
But undamaged plants are rare.
"Poison
oak, ivy and sumac are very fragile plants," says. Stems or
leaves broken by the wind or animals, and even the tiny holes made
by chewing insects, can release urushiol.
Reactions,
treatments and preventive measures are the same for all three
poison plants. Avoiding direct contact with the plants reduces the
risk but doesn't guarantee against a reaction. Urushiol can stick
to pets, garden tools, balls, or anything it comes in contact
with. If the urushiol isn't washed off those objects or animals,
just touching them--for example, picking up a ball or petting a
dog--could cause a reaction in a susceptible person. (Animals,
except for a few higher primates, are not sensitive to urushiol.)
Urushiol
that's rubbed off the plants onto other things can remain potent
for years, depending on the environment. If the contaminated
object is in a dry environment, the potency of the urushiol can
last for decades, says Epstein. Even if the environment is warm
and moist, the urushiol could still cause a reaction a year later.
"One
of the stories I tell people is of the hunter who gets poison oak
on his hunting coat," says Epstein. "He puts it on a
year later to go hunting and gets a rash [from the urushiol still
on the coat]."
Almost
all parts of the body are vulnerable to the sticky urushiol,
producing the characteristic linear (in a line) rash. Because the
urushiol must penetrate the skin to cause a reaction, places where
the skin is thick, such as the soles of the feet and the palms of
the hands, are less sensitive to the sap than areas where the skin
is thinner. The severity of the reaction may also depend on how
big a dose of urushiol the person got.
Quick
Action Needed
Because
urushiol can penetrate the skin within minutes, there's no time to
waste if you know you've been exposed. "The earlier you
cleanse the skin, the greater the chance that you can remove the
urushiol before it gets attached to the skin," says Hon-Sum
Ko, M.D., an allergist and immunologist with FDA's Center for Drug
Evaluation and Research. Cleansing may not stop the initial
outbreak of the rash if more than 10 minutes has elapsed, but it
can help prevent further spread.
If
you've been exposed to poison ivy, oak or sumac, if possible, stay
outdoors until you complete the first two steps:
·
First, Epstein says, cleanse exposed skin with generous amounts of
isopropyl (rubbing) alcohol. (Don't return to the woods or yard
the same day. Alcohol removes your skin's protection along with
the urushiol and any new contact will cause the urushiol to
penetrate twice as fast.)
·
Second, wash skin with water. (Water temperature does not matter;
if you're outside, it's likely only cold water will be available.)
·
Third, take a regular shower with soap and warm water. Do not use
soap before this point because "soap will tend to pick up
some of the urushiol from the surface of the skin and move it
around," says Epstein.
·
Clothes, shoes, tools, and anything else that may have been in
contact with the urushiol should be wiped off with alcohol and
water. Be sure to wear gloves or otherwise cover your hands while
doing this and then discard the hand covering.
Dealing
with the Rash
If
you don't cleanse quickly enough, or your skin is so sensitive
that cleansing didn't help, redness and swelling will appear in
about 12 to 48 hours. Blisters and itching will follow. For those
rare people who react after their very first exposure, the rash
appears after seven to 10 days.
Because
they don't contain urushiol, the oozing blisters are not
contagious nor can the fluid cause further spread on the affected
person's body. Nevertheless, Epstein advises against scratching
the blisters because fingernails may carry germs that could cause
an infection.
The
rash will only occur where urushiol has touched the skin; it
doesn't spread throughout the body. However, the rash may seem to
spread if it appears over time instead of all at once. This is
either because the urushiol is absorbed at different rates in
different parts of the body or because of repeated exposure to
contaminated objects or urushiol trapped under the fingernails.
The
rash, blisters and itch normally disappear in 14 to 20 days
without any treatment. But few can handle the itch without some
relief. For mild cases, wet compresses or soaking in cool water
may be effective. Oral antihistamines can also relieve itching.
FDA
also considers over-the-counter topical corticosteroids (commonly
called hydrocortisones under brand names such as Cortaid and
Lanacort) safe and effective for temporary relief of itching
associated with poison ivy.
For
severe cases, prescription topical corticosteroid drugs can halt
the reaction, but only if treatment begins within a few hours of
exposure. "After the blisters form, the [topical] steroid
isn't going to do much," says Epstein. The
American
Academy
of Dermatology recommends that people who have had severe
reactions in the past should contact a dermatologist as soon as
possible after a new exposure.
Severe
reactions can be treated with prescription oral corticosteroids.
There
are a number of OTC products to help dry up the oozing blisters,
including:
·
aluminum acetate (Burrows solution)
·
baking soda
·
Aveeno (oatmeal bath)
·
aluminum hydroxide gel
·
calamine
·
kaolin
·
zinc acetate
·
zinc carbonate
·
zinc oxide
Desensitization,
vaccines, and barrier creams have been studied over the last
several decades for their potential to protect against poison ivy
reactions, but none have been approved by FDA for this purpose.
Right
now, prevention seems the best treatment.
Getting Rid of the Plants
Poison
ivy, oak and sumac are most dangerous in the spring and summer,
when there is plenty of sap, the urushiol content is high, and the
plants are easily bruised. However, the danger doesn't disappear
over the winter. Dormant plants can still cause reactions, and
cases have been reported in people who used the twigs of the plant
for firewood or the vines for Christmas wreaths. Even dead plants
can cause a reaction, because urushiol remains active for several
years after the plant dies.
If
poison ivy invades your yard, "there's really no good news
for you," says David Yost, a horticulturist (specialist in
fruits, vegetables, flowers, and general gardening) with the state
of
Virginia
. The two herbicides most commonly used for poison ivy--Roundup
and Ortho Poison Ivy Killer--will kill other plants as well.
Spraying Roundup (active ingredient glyphosate) on the foliage of
young plants will kill the poison ivy, but if the poison ivy vine
is growing up your prize rhododendron or azalea, for example, the
Roundup will kill them too, he says.
Ortho
Poison Ivy Killer (active ingredient triclopyr), if used
sparingly, will kill poison ivy but not trees it grows around,
says Joseph Neal, Ph.D., associate professor of weed science,
Cornell University. "But don't use it around shrubs,
broadleaf ground cover, or herbaceous garden plants," he
says. Neal explains it is possible to spray the poison ivy without
killing other plants if you pull the poison ivy vines away from
the desirable plants and wipe the ivy foliage with the herbicide,
or use a shield on the sprayer to direct the chemical.
If
you don't want to use chemicals, "manual removal will get rid
of the ivy if you're diligent," says Neal. You must get every
bit of the plant--leaves, vines, and roots--or it will sprout
again.
The
plants should be thrown away according to your municipality's
regulations, says Neal. Although urushiol will break down with
composting, Neal doesn't recommend that because the plants must be
chopped into small pieces first, which just adds to the time
you're exposed to the plant and risk of a rash. "It's a
health issue," he says.
Never
burn the plants. The urushiol can spread in the smoke and cause
serious lung irritation.
The
American Academy of Dermatology recommends that whenever you're
going to be around poison ivy--trying to clear it from your yard
or hiking in the woods--you wear long pants and long sleeves and,
if possible, gloves and boots.
Neal
recommends wearing plastic gloves over cotton gloves when pulling
the plants. Plastic alone isn't enough because the plastic rips,
and cotton alone won't work because after a while the urushiol
will soak through.
Identification Please
Unfortunately,
poison ivy, oak and sumac don't grow with little picture ID badges
around their stems, so you have to know what to look for. The
famous rule "leaves of three, let it be" is good to
follow, except that some of the plants don't always play by the
rules and have leaves in groups of five to nine. To avoid these
plants and their itchy consequences, here's what to look
for.
Poison
Sumac
·
grows in boggy areas, especially in the Southeast
·
rangy shrub up to 15 feet tall
·
seven to 13 smooth-edged leaflets
·
glossy pale yellow or cream-colored berries