Echinacea for Upper Respiratory Tract Infections
BCochrane-reviewed meta-analyses suggest echinacea may modestly reduce cold duration and severity when started at symptom onset. Daily prophylactic use may reduce cold risk. Individual trial effects are small but consistently positive across multiple preparations.
The Bottom Line
Cochrane-reviewed meta-analyses suggest echinacea may modestly reduce cold duration and severity when started at symptom onset. Daily prophylactic use may reduce cold risk. Individual trial effects are small but consistently positive across multiple preparations.
Key Study Findings
Population: Children with URTI and otitis media (9 RCTs)
Population: None
Population: None
Population: children
Population: General population with respiratory infections
Population: men
Key Statistics
20
Studies
4000
Participants
Positive
Grade
Referenced Papers
Dosage & Usage
mg = milligrams · mcg = micrograms (1,000× smaller) · IU = International Units
Commonly Used Dosages
- general:
- 300-500 mg standardized extract 3x/day
- acuteuse:
- At first sign of symptoms for 7-10 days
Upper limit: No established UL; generally used for 10 days or less
Dosages Studied in Research
| Dosage | Duration | Effect | N |
|---|---|---|---|
| None | -- | Positive | 3169 |
| None | -- | Mixed | -- |
| None | -- | Positive | -- |
| None | 13.0 weeks | Mixed | 3135 |
| None | -- | Positive | -- |
| 30 ml/day | -- | Positive | 177 |
| None | -- | Neutral | -- |
| None | -- | Mixed | -- |
Best taken: At first sign of symptoms; multiple doses throughout the day
Safety & Side Effects
Reported Side Effects
- ⚠ Gastrointestinal upset (nausea, stomach pain)
- ⚠ Allergic reactions (especially in those allergic to daisies, ragweed)
- ⚠ Headache
- ⚠ Dizziness
Known Interactions
- ● Immunosuppressant medications (may counteract immunosuppression)
- ● CYP3A4 substrates (may alter metabolism of various drugs)
- ● Caffeine (may slow caffeine metabolism)
- ● Anabolic steroids and methotrexate (increased hepatotoxicity risk)
Tolerable upper intake: No established UL; generally used for 10 days or less
Always consult your healthcare provider before starting any supplement.
Frequently Asked Questions
Does Echinacea help with Upper Respiratory Tract Infections?
How much Echinacea should I take for Upper Respiratory Tract Infections?
Are there side effects of Echinacea?
How strong is the evidence for Echinacea and Upper Respiratory Tract Infections?
Related Evidence
Other ingredients for Upper Respiratory Tract Infections
FDA Disclaimer: These statements have not been evaluated by the Food and Drug Administration. The products and information on this website are not intended to diagnose, treat, cure, or prevent any disease. The evidence grades presented are based on our analysis of published peer-reviewed research and do not constitute medical advice. Always consult your healthcare provider before starting any supplement regimen.