Products
In many countries, the special extract Ze 339 from the leaves of the common butterbur ( L., Asteraceae) has been approved for the treatment of hay fever since 2003 (Tesalin, Zeller Heuschnupfen). Since 2018, the drug is also available without a doctor’s prescription. The list reclassification took place in September 2017.
Ingredients
Petasins, esterified sesquiterpenes of the eremophilane type, are thought to be responsible for the effects. These include petasin, isopetasin, and neopetasin, and the sulfur analogs S-petasin, S-isopetasin, and S-neopetasin, which are present in a smaller proportion. Here, S stands for sulfur and does not refer to the configuration. The ingredients inhibit the synthesis and release of leukotrienes and histamine and are anti-inflammatory. The extract Ze 339 is standardized to petasins. The leaves of a specially cultivated species rich in ingredients are used for its preparation, and not the roots (rhizomes) as in other medicines. Butterbur should not be used as a tea or in the form of other unprocessed preparations because the plant and the medicinal drug contain pyrrolizidine alkaloids, which may be liver toxic, carcinogenic, and genotoxic, especially with prolonged use. During the extraction process with liquid carbon dioxide and subsequent thin-layer chromatography, the finely chopped leaves are freed from these toxic alkaloids.
Effects
Butterbur extract was effective against the symptoms of hay fever such as itching of the nose and eyes, runny and stuffy nose, and reddened eyes in the studies conducted. The effects were reported to occur quickly, as early as 30 to 90 minutes after ingestion. Efficacy has been evaluated in controlled clinical trials comparing the antihistamines cetirizine and fexofenadine with placebo, and in postmarketing studies. These studies suggest efficacy similar to that of antihistamines.
Indications
For the treatment of allergic rhinitis (hay fever).
Dosage
According to the SmPC. Tablets are taken two to three times daily, regardless of meals.
Contraindications
The drug is contraindicated in case of hypersensitivity. Full precautions can be found in the drug label.
Interactions
Interactions with other drugs are not known to date. In vitro studies have shown no interaction with cytochromes P450 or P-glycoprotein to date.
Adverse effects
The most common potential adverse effects include gastrointestinal discomfort such as nausea, diarrhea, and abdominal pain.