This meta-analysis examines the effect of Echinacea purpurea on the prevention of respiratory tract infections (RTIs) and the reduction of antibiotic use. A total of 30 clinical trials with 5,652 participants were analyzed to evaluate the protective effect of Echinacea against respiratory tract infections and their complications.
The results show that the regular intake of echinacea:
- Reduces the risk of a respiratory infection by 32 % (RR = 0.68),
- The risk of recurrent infections reduced by 40 % (RR = 0.60),
- Complications of RTIs reduced by 56 % (RR = 0.44),
- Reduces the need for antibiotic therapy by 40 % (RR = 0.60) and
- The total number of antibiotic therapy days reduced by 70 % (IRR = 0.29).
Alcoholic extracts of freshly harvested Echinacea purpurea were particularly effective, reducing the need for antibiotic therapy by 80 %. Side effects were rare and not more frequent than in the placebo group.
Conclusion: Echinacea is a safe and effective option for the prevention of respiratory tract infections and can make an important contribution to reducing the use of antibiotics.
Background:
Respiratory tract infections (RTIs) are among the most common diseases worldwide and are the main cause of antibiotic prescriptions. As many of these infections are viral in nature, antibiotic use is often unnecessary and contributes to the global resistance problem. Echinacea purpurea has immunomodulatory and antiviral properties that could potentially help prevent RTIs and reduce antibiotic use.
This meta-analysis investigates whether the intake of echinacea:
1. reduced the frequency of RTIs,
2. prevents recurring infections,
3. reduces complications such as bacterial superinfections and
4. reduce the use of antibiotics.
Methodology:
- Data basis: 30 clinical studies with a total of 5,652 participants.
- Data sources: EMBASE, PubMed, Google Scholar, Cochrane DARE, clinicaltrials.gov.
- Parameters analyzed:
- Occurrence of RTIs (at least one episode),
- Recurrent infections,
- Occurrence of RTI complications (e.g. sinusitis, bronchitis),
- Number of antibiotic treatments and days.
- Statistical analysis: Calculation of risk (RR) and odds ratios (OR) as well as individual risk reduction (IRR) with random-based models.
Results:
1. Reduction in the frequency of infection:
- Regular use of echinacea reduced the risk of respiratory tract infections by 32 % (RR = 0.68, p < 0.01).
- The probability of experiencing at least one RTI during the study period decreased by 25 % (RR = 0.75, p < 0.01).
2. Reduction of recurring infections:
- Recurrent RTIs occurred 40% less frequently in the echinacea group (RR 40 % less frequently (RR = 0.60, p < 0.01).
- The strongest effect was seen with long-term use (> 3 months).
3. Fewer complications:
- Complications such as sinusitis, bronchitis or middle ear infections were reduced by 56 % (RR = 0.44, p < 0.01).
- Children in particular benefit from the preventive use of echinacea.
4. Reduce the use of antibiotics:
- The need for antibiotic therapy was reduced by 40 % (RR = 0.60, p < 0.05).
- The total number of antibiotic therapy days was reduced by 70 % (IRR = 0.29, p < 0.02).
- The strongest effect was achieved with alcoholic Echinacea purpurea extracts(reduction of 80 %).
5. Safety and compatibility:
- No serious side effects.
- Side effects (mostly mild gastrointestinal complaints) occurred just as frequently with echinacea as in the placebo group (RR = 1.01, p = 0.90).
Discussion:
The results show that echinacea not only reduces the risk of respiratory infections, but can also reduce their severity and the need for antibiotic treatment.
The mechanisms behind these effects could include:
- Direct antiviral activity: Echinacea inhibits the replication of enveloped viruses such as influenza, RSV and coronaviruses.
- Immunomodulation: Activation of interferon signaling pathways and promotion of immune cell migration.
- Inhibition of inflammation: Reduction of pro-inflammatory cytokines such as TNF-α and IL-6.
Alcoholic extracts from freshly harvested Echinacea purpurea were particularly effective, while hydrophilic (aqueous) preparations were less effective.
Conclusion:
The results of this meta-analysis provide strong evidence that Echinacea purpurea is an effective and safe option for the prevention of respiratory infections. In addition, echinacea could play a key role in reducing the overuse of antibiotics and thus contribute to combating antibiotic resistance.
Future studies should focus on the optimal dosage and the combination with other immunomodulatory strategies.