Suggested Dosing
Migraine
50 mg PO TID OR 100 mg PO BID x4 weeks, THEN
50 mg PO BID
Allergic Rhinitis
50 mg extract generally standardized to contain 7.5 mg petasins PO BID
Leaf extract: 8 mg of petasin, 1 tablet PO TID-QID
Suggested Uses
Seasonal Allergic Rhinitis (Hay Fever)
Migraine prophylaxis
Adverse Effects
None reported
Warnings
Cautions
Contains pyrrolizidine alkaloids (especially in roots), which may be carcinogenic & hepatotoxic (commercial preparations are generally pyrrolizidine-free)
Pregnancy & Lactation
Pregnancy Category: N/A
Lactation: N/A
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Metabolism:
Excretion:
Mechanism of Action
Contains Petasin, a sesquiterpene ester, that has leukotriene inhibitory function
Efficacy: clinical studies show efficacy similar to fexofenadine in relieving hay fever symptoms & greater effctivity over placebo in migraine prophylaxis