Efficacy and safety of Echinacea purpurea in treating upper respiratory infections and complications of otitis media in children: Systematic review and meta-analysis

Abstract

Background: Echinacea purpurea is widely utilized in dietary supplements, nutraceuticals, and herbal medicine, yet its effectiveness and safety for children remain debated.

Objective: To evaluate the effectiveness and safety of E. purpurea in the treatment of upper respiratory tract infection (URTI) and otitis media (OM) in children.

Data sources: Embase, Cochrane Central Register of Controlled Trials (CENTRAL), ClinicalTrials.gov, PubMed from January 2000 to December 2023.

Methods: This systematic review and meta-analysis were conducted and reported according to the PRISMA 2020 Checklist and Cochrane Training 2022 guidelines.

Results: 9 randomized controlled trials with 1518 participants in the treatment group, 1651 participants in the placebo control group, met the selection criteria. Products derived from E. purpurea are highly diverse, utilizing different plant parts such as roots, leaves, and flowers, available in various dosage forms like capsules and extracts, and manufactured in numerous countries worldwide. Risk of bias was assessed according to the PEDro scale with 3 studies of excellent quality, 5 studies of high quality and 1 study of moderate quality. The meta-analysis found that E. purpurea significantly benefits URTI, reducing treatment duration (SMD = -0.19, 95 % CI [-0.30; -0.09], p < 0.01), incidence (RR = 0.81, 95 % CI [0.75; 0.87]), and antibiotic use (RR = 0.18, 95 % CI [0.13; 0.25], p < 0.01). However, adverse events were moderately increased (RR = 1.38, 95 % CI [1.08; 1.78]), though generally mild. For OM, E. purpurea lowered episode incidence (RR = 0.56, 95 % CI [0.44; 0.73], p < 0.01) but did not shorten treatment duration (p = 0.10). Its effectiveness may be limited due to OM's bacterial etiology, often requiring antibiotics. While E. purpurea may help reduce recurrence, it is unlikely to speed recovery. Further research on optimal formulations and dosages is needed. The publication bias of pooled results as assessed by the funnel plot showed that the studies had certain bias, largely due to heterogeneity between studies.

Conclusion: The meta-analysis of nine studies found that E. purpurea was effective in reducing the duration of treatment, the incidence of episodes, and antibiotic usage for URTI in children, with some positive effects on OM. This study systematically evaluates the efficacy and safety of E. purpurea in treating URTI and OM in children, providing evidence-based insights to guide clinical decisions and inform healthcare professionals and parents considering its use. However, the safety profile remains unclear, particularly regarding adverse events. Further research is required to standardize methodologies and confirm these results.

Keywords: Children; Common cold; Echinacea purpurea; Otitis media; Upper respiratory tract infection.