Poison ivy: How effective are available treatments?
In this study, only one treatment approach significantly reduced pruritus. Three approaches were often associated with recurrences of rash or symptoms.
Since only 2 patients used topical soaps following their initial clinician visit, the associations between use of these products and longer duration of signs and symptoms and with recurrence of signs and symptoms, although statistically significant, should be viewed with skepticism and with an eye toward possible confounders (eg, people who used these agents may have been more likely to notice and record minor symptoms). Furthermore, these agents have been effective only when used before or at the onset of the rash.
Study limitations. The study has a number of limitations. It had a high drop-out rate. Some patients might not have had poison ivy, but it is generally considered easy to diagnose with accuracy. We cannot be sure that all of the enrolled patients had Rhus dermatitis. Enrollment was based on the clinical impression of the patients’ primary care clinicians. The sample size reduced the power of the study to detect small differences in treatment effects and prevented more complex analyses (eg, combinations of medications, interactions).
The possibility of self-selection bias, weaknesses of the cohort design, and patient-reported outcome measures were additional limitations. The study was also carried out in a single southwestern state, which may not be representative of some other locations. However, it is one of only a few studies published on Rhus dermatitis and possibly the only one conducted in primary care settings.
CORRESPONDENCE
Cara Vaught, MPH, University of Oklahoma Health Sciences Center, Department of Family and Preventive Medicine, 900 NE 10th Street, Oklahoma City, OK 73104; cara-vaught@ouhsc.edu.
ACKNOWLEDGEMENT
The authors thank the Oklahoma Physicians Resource/Research Network (OKPRN) and the OKPRN clinician members (as well as their staff and patients) for their contributions to this study. The authors also thank Bradley Long, Matthew Marr, and Kellie Hetherington for their involvement in the data collection for this study.
