Butterbur for Allergic Rhinitis?

Butturbur roots have long been a constituent of herbal remedies, but the use of the leaves is relatively recent. Lab studies suggest that an extract of the leaves inhibits the formation of a protein involved in the inflammation associated with allergies, while stimulating production of prostaglandins that also reduce inflammation. So it seems that allergic rhinitis might be a fruitful field for a clinical study.

Such a study was done at the Allergy Clinic in Landquart, Switzerland. 330 patients with intermittent allergic rhinitis were allocated randomly to take either butterbur extract (8 mg three times a day), fexofenadine (Telfast®, 180 mg once daily), or placebo, for 2 weeks.

Both butterbur and fexofenadine improved total symptoms scores for allergic rhinitis significantly, compared with the placebo; there was no difference in the effectiveness of the two active substances. Full recovery was reported in 28% of patients on butterbur, 31% of those on fexofenadine, and 13% of those on placebo. Relief was experienced 24 hours with both butterbur and fexofenadine. Side effects were mild, and reported in 7%, 9%, and 6.5% of those on butterbur, fexofenadine, and placebo, respectively.

These findings indicate that an extract of butterbur may possibly help allergic rhinitis sufferers. As withal herbal extracts, it’s important to ensure the purity and content uniformity of the dosage form. The product used in this study was Ze339, made by Zeller AG, a Swiss company. However, it should be realized that another controlled study, conducted in Scotland, showed no benefit of Ze339 on symptoms of intermittent allergic rhinitis. This has to be balanced against yet a third study, done by the Swiss investigators, showing it’s effectiveness.

Battling study results are not uncommon in new drug development. That’s why the FDA demands rigidly-controlled, well-designed, well-conducted studies that are subject to monitoring by experts in the discipline. This allows them to place more reliance on the results from good studies, and less on poor studies. We’ll see what happens with butterbur, eventually.