IVY POISONING, a skin disease or dermatitis characterized by erythema, wheals, papules, vesicles, pustules, bullet, or a combina tion of two or more of them, with an addition of crusting and excoriations. It is caused by Rkus toxicodendron (poison ivy), a climbing plant and a small tree or shrub (poison oak) are the most common causes in the eastern part of the United States, and also in the West. In the, Middle States the poison sumach seems to be the more commonly poisonous one Rhus venenata (poison dogwood, sumach elder). The nettle commonly seen in the woods and unkept meadows, the primrose (Primula ob conica), the oleander (Nerium oleander), the rue (Ruta), the smartweed (Polygonum punc tatum) are the most common ones known, but there are many others.
The inflammatory reaction produced by Rhus toxicodendron (poison ivy) is quite typical and so commonly seen in the springtime and sum mer that even the ordinary person may make an accurate diagnosis. The disease starts upon the exposed parts primarily. The hands and wrists or forearms are the first members at tacked usually, then follow the face, the geni talia, and anal regions; barefooted children are great sufferers also. It is said that toxico dendric acid, a volatile substance, is the cause, although it has not been specifically proved. Many persons who have had at one time or another severe attacks, have found that in passing through the woods, or anywhere in the proximity of the plant, they may have a recurrence of the attack, even though the plant is not touched. As the years pass and there has been no contact made with the ivy, this peculiar susceptibility to the air-laden poison becomes almost nil. There is a belief that after one attack of some severity there is a recurrence at the same time the following year, regardless of any proximity to plants. Prob ably these are really cases of vesicular eczema. There is a serious tendency in some instances of ivy poisoning to a persistency toward a chronic condition, which, according to our present knowledge of eczema, may be classed as such.
Persons prone to attacks of eczema are very susceptible to the poison. There are in dividuals too, who from childhood have never been subject to plant poisoning, but with change of climate or methods of living, suddenly are rendered susceptible. Then there are those who seem to preserve an immuity to poisonous plants, handling them with perfect impunity.
The poison ivy is a shrub which usually climbs by means of rootlets over rocks, walls, and trees, sometimes low and erect. Leaves are divided into three somewhat four-sided pointed leaflets. This much dreaded plant is often confused with the beautiful Virginia creeper; the two can be distinguished by the three-divided leaves of the ivy and the usually five-divided leaves of the creeper. It is sup posed that the ivy is especially harmful in the night or when the sun is not shining directly upon the plant. A more or less mild attack may be ushered in by a burning or itching of the skin. Within a few hours up to 24 or 48, an erythema may appear, followed by swelling, with vesicles, or the vesicles may arise with little areola. The vesicles may be few in number, or clustered in great multitudes on the affected parts. At first they may be tense, but often rapidly become flaccid, rup turing easily. The yellowish serum in the vesicles doubtless carries the poison, as it seems to inoculate nearby previously unaffected areas, spreading the disease. The lesions often de velop in streaks or stellate patches slightly raised, surmounted by vesicles. The parts may swell to enormous proportions. The face be comes quite distorted, the eyelids suffer, and conjunctivitis is not uncommon. The suffering from the itching and burning is intolerable. The dermatitis usually progresses to a certain point before regression takes place. Some abortive cases clear up rapidly. After the vesicles rupture and dry the erythema and swelling slowly disappear. The disease may last but a few days or remain from several weeks to several months. Its common dura tion is from 10 days to three weeks. It often leaves in its wake a mass of freckles or pig mentation such as often follows a sunburn.
In treatment the large vesicles should be evacuated, the secretion being prevented from reaching unaffected parts. Compresses of boric acid or phenol lotions may be used, or a solu tion of thiosulphite of soda. Lotions with powder suspensions are comforting. Hot com presses of salt and baking soda solution are helpful. A standard lotion is a compound resorcin, one containing boric acid and resorcin, a a 3 i; pulv. zinc' oxidi, 3 i.; aq. calms q.s. ad 3 viii. In mild cases healing may he ob tained by a simple astringent ointment such as angmentum, zinci oxidi, but ointments as a rule are not so pleasant as lotions.