The effect of open-label placebo on allergic rhinitis symptoms: A systematic review and meta-analysis of randomized controlled trials.

The evidence regarding the open-label placebo effect on allergic rhinitis symptoms remains uncertain. Open-label placebo significantly reduced the frequency of symptoms in allergic rhinitis patients with similar safety profiles; however, there was no effect on the severity of symptoms and impairment due to symptoms. The statistically significant impact on symptom frequency can be considered not clinically significant.