Curtisa G, Lewis AC. Treatment of severe poison ivy: a randomized, controlled trial of long- versus short-course oral prednisone. J Clin Med Res. 2014; 6(6):429–434. [ PMC free article] [ PubMed] [ Google Scholar] Eating the plants can cause severe internal irritation, and inhaling particles of urushiol released by burning poison ivy, oak, or sumac can cause swelling of the respiratory passages, which can even result in death. These cases require specific and immediate medical treatment. Control hog-peanut and ground nut are vines with alternate leaves (like poison-ivy) but with clusters of small whitish to purplish or brownish flowers like those of the sweet pea.

Although the leaflets are somewhat oval, they vary greatly in shape and size. Their margins vary from perfectly smooth ( Figure 3A) to finely or coarsely toothed ( Figure 3D), to deeply and irregularly lobed ( Figure 3E). Undersides of the leaflets may be finely hairy all over, or just along the veins and veinlets, or may be virtually without hairs. Gladman AC. Toxicodendron dermatitis: poison ivy, oak, and sumac. Wilderness Environ Med. 2006; 17(2):120–128. Accessed September 4, 2020. [ PubMed] [ Google Scholar]

Lofgran T, Mahabal G. Treasure Island, FL: StatPearls Publishing; 2020. Toxicodendron toxicity. StatPearls. Last Update: April 19, 2020. https://www.ncbi.nlm.nih.gov/books/NBK557866/ Accessed 17 Sep 2020. [ Google Scholar] Templeton D. Climate change is making poison ivy bigger and badder. https://www.post-gazette.com/news/health/2013/07/22/Climate-change-is-making-poison-ivy-grow-bigger-and-badder/stories/201307220149 22 Jul 2013. Pittsburg Post Gazette. Accessed 22 Sep 2020. Figure 11. Smooth sumac leaves have eleven to thirty-one leaflets. Note that the leaflets have teeth along the edges.

Poison-ivy ( Rhus radicans L.) is widespread throughout southern Ontario and reaches north approximately as far as Cochrane and Kenora. It is found most abundantly, however, south of a line from the north shore of Lake Huron through North Bay. This includes the densely populated portions of the province and the popular vacation areas. The plant is often mistakenly called "poison oak", but the true poison oak occurs only in the southern and Pacific states of the U.S.A. and not in Ontario.Approximately 10 to 15 percent of people will have reactions severe enough to require medical treatment, often in the form of oral or injected low-dose steroids administered by a doctor. Seek medical help if the rash becomes infected, covers a large part of the body, causes swelling of the face or other sensitive areas, or causes difficulty with swallowing or breathing. Nevertheless, when in doubt, avoid touching the unknown plant until you have obtained help to identify it. Control of Poison Ivy While there is no entirely satisfactory treatment for TCD other than the “tincture of time,” longer-course glucocorticoid therapy, such as triamcinolone or prednisone, has been shown to be effective in relieving symptoms associated with TCD. 8 Short courses of low-dose methylprednisolone (so-called “dose paks”) are too brief and too weak to offer effective relief. Glucocorticoids should be administered using a 2- to 3-week taper starting with 60mg daily (preferably taken in the morning with food to avoid gastritis) for five days that is reduced to 40mg daily for five days and then down to 20mg daily for five days. 9 , 8 Contraindications for glucocorticoids include concurrent infection, peptic ulcer disease, poorly controlled hypertension, congestive heart failure, and diabetes. 9 Dementia can also be made worse with systemic steroids (so-called “steroid psychosis”). 9 Less serious side effects of systemic glucocorticoids include an increase in appetite, retention of fluid (edema), irritability, and insomnia. Adrenal suppression associated with prolonged systemic steroid use is rarely a problem when using a 2- to 3-week course of glucocorticoid therapy for poison ivy. 9 Many plants have been mistaken for poison-ivy because their leaves may also consist of 3 leaflets. These can be distinguished from poison-ivy as follows.

These herbicides can be bought in various concentrations and under many different trade or brand names. Therefore, it is not feasible in this Factsheet to give detailed instructions for mixing and application of each kind. Detailed directions for its use are printed on the label on every container of each herbicide. Follow the manufacturer's directions. For safety's sake, read the label carefully and observe all precautions printed on it. These herbicides are usually most effective if applied anytime from when the foliage is fully developed until the plants begin to go dormant, usually from about June 15 to July 31. Some regrowth of the weed may occur after it has been treated. Therefore, examine the area periodically and the repeat treatment as often as any regrowth appears. In this manner, poison-ivy can often be eliminated from an area. Nancy Loewenstein, Extension Specialist, School of Forestry and Wildlife Sciences, Auburn University; Amber C. Dunn, former 4-H Regional Extension Agent; and Mark D. Smith, Professor, School of Forestry and Wildlife Sciences, Auburn University.Hauser SC. New York, New York: Lyons & Burford Publishing Co.; 1996. Nature’s Revenge. [ Google Scholar]

A. Low-growing form with short erect stems and a flower cluster from the axil of one compound leaf.About 85 percent of people are allergic to urushiol, the oily compound responsible for the skin reaction. Urushiol is found in all parts of these plants. Simply touching the leaves may expose you to the oil, and additional oil is released when plant parts are crushed or damaged. The oil resists breakdown and may cling to clothing, tools, and pet fur for long periods of time, even a year or more. Exposure to the oil on these secondary sources can also cause an allergic reaction.