Abstract
The aim of this study was to survey the exact benefit of this herb in the management of
clinical and laboratory signs and symptoms of allergic rhinitis. In a randomized double blind
clinical trial, 74 patients with the signs and symptoms of allergic rhinitis and a positive skin
prick test were selected and randomly divided into 2 groups who were taken Urtica dioica
150-mg, Urtidin® F.C Tablet) or placebo for one month. Their signs and symptoms, eosinophil
percentage on nasal smear, serum IgE, and interleukin IL-4, IL-5, interferon- γ) levels were
recorded.
Forty patients completed the trial. Based on the Sino- Nasal Outcome Test 22 SNOT-22), a
significant improvement in clinical symptom severity was observed in both groups P < .001).
Furthermore, a statistically significant reduction in mean nasal smear eosinophil count was
observed after treatment with Nettle P < .01). However, the mean IgE and IL4 and IL5 levels
in the study group before and after treatment with Nettle saw no significant changes P > .1).
Intergroup pre- and post-treatment laboratory findings suggested that there was a significant
difference in post-treatment changes of mean IFN γ levels between the study and placebo
group P = 0.017). Although the current study showed certain positive effects of Nettle in the
management of allergic rhinitis on controlling the symptoms based on the SNOT-22, similar
effects were demonstrated by placebo as well. We believe that our limitations underscore the
need for larger, longer term studies of Nettle for the treatment of allergic rhinitis.
