Studies on poison ivy and other dermatitis-producing plant parts wherein active, resinous principles are suspended in aqueous solution

Abstract

1. 1. A method is presented for the preparation of a new product from poison ivy, poison oak, poison sumac, primrose, and the like and pollen oils, whereby the active principle is suspended in aqueous solution. 2. 2. The new product suspended in aqueous solution is shown to be nontoxic and nonirritating. 3. 3. The alum precipitated pyridine-ivy complex suspended in saline solution is as active as an equivalent dilution of the alcoholic ivy extract. 4. 4. Sensitive patients treated phylactically with the alum precipitated pyridine-ivy “extract” were relieved by the second to fifth injection. 5. 5. A group of twelve patients treated prophylactically in 1943 with the alcoholic extract with poor results were treated in 1944 with the alum precipitated pyridine-ivy “extract” with good clinical results. Sixteen other sensitive individuals experienced a season practically free from poison ivy dermatitis following injections of a precipitated pyridine-ivy “extract.” 6. 6. Guinea pigs were sensitized by one intraperitoneal injection of the alum precipitated pyridine-ivy “extract” as shown by positive patch tests (twenty-one days after the sensitizing injection) to 3 drops of the concentrated alum precipitated pyridine-ivy “extract” or alcoholic-ivy extract.