Supplement
Butterbur is a shrub whose root extract contains petasins, compounds that block histamine receptors and slow the body's production of inflammatory leukotrienes. People mostly look at it for hay fever, and trials found seasonal allergy symptoms eased about as much as with cetirizine, without sedation. The evidence is strong overall but moderate for symptoms specifically, and one migraine trial also found fewer attacks than placebo.
- Updated
- How we grade
- 1 study cited
- Best evidence
- Grade B
- Conditions studied
- 2
- Outcomes
- 2
- Graded outcomes
- 0200
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Migraine Frequency RCT (n=245, PMID: 15623680): 75mg twice daily reduced migraine attacks by 48% vs 26% placebo. AAN/AHS guidelines previously rated it Level A for migraine prevention. | Improves (the measure goes down) | Moderate effect | 400 people |
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Allergy Symptoms Multiple RCTs: Butterbur comparable to cetirizine (Zyrtec) for seasonal allergy relief without sedative effects. 8mg petasin 4x/day effective. | Improves (the measure goes down) | Moderate effect | 500 people |
Key findings
- Migraine FrequencyImproves (the measure goes down)
- Allergy SymptomsImproves (the measure goes down)
Studies cited
1 study from PubMed