Fragrant sumac ( Rhus aromatica) is often mistaken for poison oak, and both grow in similar habitats. One difference is that the leaflets of fragrant sumac are attached at a single point, while the terminal leaflet of poison oak has a short stem. Also, the fruit of the fragrant sumac plant is red (figure 10). 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

Nevertheless, when in doubt, avoid touching the unknown plant until you have obtained help to identify it. Control of Poison Ivy 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.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. However, all of the herbicides which kill poison-ivy may also kill or damage other plants growing nearby. If poison-ivy is growing among perennial ornamentals, in a hedge, or entwined about a favorite tree, one must resort to cutting and digging to destroy it. Wear gloves and other protection while cutting and grubbing. Take care also to prevent other persons from being inadvertently contaminated by the tools, the roots, stems and leaves, or by the smoke if the material is burned (see section on Harmful Effects).

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. TCD places a financial burden on our economy and utilizes substantial healthcare resources. For example, outdoor occupations related to agriculture, forestry, and firefighting are at high risk of exposure to poison ivy, and when affected, these workers incur significant monetary expense for worker disability and medical treatments.TCD is responsible for 10 percent of the total US Forest Services lost work time due to injuries. 17The leaves of poison ivy (figure 1) and poison oak (figure 2) have three leaflets. This is where the adage leaves of three, let it be comes from. The leaflets are commonly 2 to 8 inches long and 3⁄4 to 5 inches wide, and they have scattered, jagged teeth along the edges. Some have a larger tooth or lobe close to the bottom edge, giving them a mitten-like shape. Gladman AC. Toxicodendron dermatitis: poison ivy, oak, and sumac. Wilderness Environ Med. 2006; 17(2):120–128. Accessed September 4, 2020. [ PubMed] [ Google Scholar] Individuals vary greatly in susceptibility to ivy poisoning and many have never suffered any ill effects. However, those in the latter category should not take for granted that they are immune for all time. Cross Reactivity Caution! Even at this stage take care as poisoning may be brought about by handling the dead plants. Several herbicides (chemical weed-killers) have been used effectively for providing good control of poison-ivy: