A team of Swiss researchers found that butterbur extract is an effective antihistamine without any side effects. Mr John de Carpentier said,presumably it contains an active biochemical agent, otherwise it would not work - and therefore it is possible that this might react with other medications.
It was used in treating hayfever The researchers gave 154 hayfever patients either butterbur extract tablets or the usually used non-sedating antihistamine called cetirizine. After three weeks, the treatments had achieved similar effects.
Butterbur is a perennial shrub, found throughout Europe as well as parts of Asia and North America, that has been used medicinally for centuries. During the Middle Ages it was used to treat plague and fever. In the 16th century its use was noted in treating cough, asthma, and skin wounds.
Currently, it is used in the treatment of migraines. It has also been used successfully in preventing gastric ulcers, and in treating patients with irritable bladder and urinary tract spasms. Extracts are prepared from the rhizomes, roots, and leaves.