- Toxicodendron radicans L.
- Rhus toxicodendron
- Poison Oak
- Rhus radicans L.
- Rhus diversilobs L.
- Cashew family
Poison Ivy is a climbing vine, Rhus toxicodendron, which on
contact produces a severe form of dermatitis. Rhus species contain
urushiol, and extremely irritating oily resin. Urushiol may also be
a potent sensitizer since in many cases subsequent contacts produce
increasingly severe reactions.
Poison Oak is a climbing vine, Rhus radicans or R diversiloba,
closely related to poison ivy and containing he same active principle.
The symptoms and treatment are identical with those for poison ivy.
The oily resin (sap) in the leaves, flowers, fruit, stem bark and
roots of poison ivy or poison oak causes a dermatitis resulting from
irritation or sensitization of the skin. There is no absolute immunity
although susceptibility varies greatly even in the same individual.
The plant is poisonous even after long drying, but is particularly
irritating in spring and early summer when it is full of sap.
The poisons can be conveyed to the skin in ways other than direct
contact. Some have contracted the poison simply by petting an animal
that has been in contact with the plant. Those that are highly sensitive
to poison ivy or oak can be infected by inhaling smoke from a nearby
brush fire where the plant is burning. Severe cases of mouth poisoning
have been reported when children have eaten the leaves or grayish
berries of the plant.
If you suspect that you have accidentally handled poison ivy or brushed
against it, wash your skin immediately. Lather several times and rinse
in running water after each sudsing. Wash clothing, gear, or pack
material in plenty of soapy water. Stubborn cases that do not respond
to proper treatment are often due to repeated contact with contaminated
Poison ivy or oak grows in many parts of the United States. In all,
there are 60 varieties of poisonous plants indigenous to the United
States. Apart from poison ivy, the most common are oak-leaf poison
ivy, western poison oak, and poison sumac Rhus vernix). Other botanical
skin irritants include: goldenrod, crabgrass, nettle, table grass,
dog fennel, hollyhock, and Indian mallow.
An interval of time between skin contact of poison and first appearance
of symptoms, varying from a few hours to several days and depending
on sensitivity of the patient and possibly condition of the skin.
Moderate burning and itching sensation soon followed by small blisters;
later manifestations vary. Blisters usually rupture and are followed
by oozing of serum and subsequent crusting.
Contact with uncovered skin produces redness, rash, swelling, blistering,
and intense, persistent itching in sensitive people. Exposed areas
such as the hands, arms, and face are most commonly the first to be
affected. Scratching transmits the inflammation, via the hands, to
other parts of the body.
Mild cases are signaled by a few small blisters that occur on the
hands, arms, or legs. Treat mild cases by applying compresses of very
hot, plain water for brief intervals. Also may apply compresses soaked
in a dilute Burrow's solution (1 pint to 15 pints of cool water).
Purchase Burrow's solution at the drugstore.
Severe cases of poison ivy or oak are signaled by many large blisters,
acute inflammation, fever, or inflammation on the face or genitals.
In severe cases, contact the doctor. He will be able to relieve the
discomfort and guard against secondary infection until the attack
Wear protective clothing if trekking through heavy underbrush: trousers,
long sleeves, shoes, socks and gloves. Once in contact with poison
ivy, these are not safe to re-wear until they have been laundered
or dry cleaned.
The best treatment for poison ivy or oak is prevention. Learn to
recognize, and avoid, this harmful plant. Its leaves always grow in
clusters of three, one at the end of the stalk, the other two opposite
each other. Memorize the poison ivy rhyme: "Leaflets three, let it
Dosages here are for adults only. Adjust dosage for age and weight.
Vitamin C, 3,000-8,000 mg. per day, helps to prevent infection and
Calamine lotion, used as directed on the label, contains calamine,
phenol, and zinc oxide and has a drying effect for faster healing.
Aloe vera gel, used as directed on the label, may relieve itching.
Vitamin A, 25,000 IU per day, is needed for healing of skin tissues
and boost immune system.
Vitamin E or enzyme cream, as directed on the label, aids in healing
and prevents scarring.
Zinc, 80 mg. per day, is needed for repair of skin tissues.
- Beech, American
- Dock, common narrow-leaf
- Fern, sweet
- Gum plant
- Heart's ease
- Hyssop, yellow giant
- Impatiens pallida or biflora
- Labrador tea
- Lettuce, wild
- Oak, Northern red
- Oak, white, bark (tea made with white oak and lime water. Apply
a wet bandage of this and change as often as it dries)
- Solomon's seal
- Thistle, Canada
- Willow, white
- Witch hazel
See the doctor if fever occurs, or if a widespread rash involving
the eyes, mouth, or genitals occurs.
To kill poison ivy plants: make a spray solution with 3 lb.
salt to 1 gallon of slightly soapy water. Sprinkle the plants; it
may take 3 applications. If you pull out or cut the vines, avoid direct
contact. Clean tools afterward and wash gloves.
Remove all clothing and shoes, and immediately us laundry soap and
water or alcohol to deter the attack. This procedure is useless if
not done immediately. Poison ivy residue has been noted on clothing
for up to 1 year unless washed thoroughly.
Tepid water is used to provide symptomatic relief from itching and
burning. In some cases the affected area is massaged with water as
hot as can be tolerated for 1 or 2 minutes. The relief from itching
is dramatic and may last several hours.
Common narrow-leaf dock (Rumex crispus) is used medicinally for the
itch. The leaves are boiled in vinegar until the fiber is softened
and then combined with lard or petroleum jelly to make a simple ointment.
Never ingest Poison Ivy.
Contact with this plant may cause allergic reaction, rash.