Safety of Oral Echinacea Preparations: Systematic Review and Meta-Analysis in the Context of Therapeutic Benefit

Full abstract

Read the full abstract

Recent literature has assessed the potential of Echinacea products to reduce respiratory tract infections (RTIs) and antibiotic use but has not comprehensively evaluated safety within a risk-benefit framework. Our systematic review and meta-analysis reviewed relevant databases for adverse events (AEs) in clinical trials comparing oral Echinacea (all species and preparations) with placebo, active or no-treatment groups. AEs were classified by System Organ Class (SOC) and compared with individual case safety reports (ICRs) from EudraVigilance (EVDAS). Across 48 clinical studies (N = 10,115), 2,396 AEs were reported. AE occurrence was lower in Echinacea groups compared with any control (22.7% vs. 24.8%, p = 0.014) and to placebo control only (29.1% vs. 32.3%; p = 0.005). In therapeutic settings, after excluding pressed juice formulations, Echinacea significantly reduced AEs by up to 21.1% (19.8% vs. 25.1%; p < 0.0001). Preventive studies in healthy participants showed comparable AE rates between Echinacea and control groups (21.3% vs. 22.3%; p = 0.411). Serious AEs (SAEs) accounted for 0.09% and 0.08% of events for Echinacea and any control, respectively; no fatal SAEs were reported. Spontaneous EVDAS reports mostly concerned gastrointestinal (17.7%), general (13.1%), and nervous system disorders (10.3%, e.g. headache), whereas skin and subcutaneous tissue events (16.1%) were less prominent in clinical trials, which predominantly investigated high-quality pharmaceutical extracts.Principally, oral Echinacea products demonstrate a high level of safety, with preparation-dependent qualitative differences. Pharmaceutical-grade ethanolic extracts showed further reductions in AEs versus control, possibly reflecting clinical efficacy and supporting positive risk-benefit evaluation for RTI management and antibiotic stewardship.