Intestinal spasmolytic effects of STW 5 (Iberogast®) and its components

Functional gastro-intestinal diseases as the irritable bowel syndrome are very common in the population and are characterized by a broad spectrum of symptoms which mostly are related to spastic or paralytic intestinal function without defined histopathological changes of the tissue. Due to the multifactorial pathogenesis a multifactorial therapy with multi-target action seems to be reasonable. STW 5 (Iberogast®), its constituent herbal extracts and some isolated compounds were used in an in vitro model provided by intestinal samples from guinea pig in order to test their activity on histamine-induced contractions and spontaneaous motility, respectively. For comparison the known spasmolyticum papaverine was used. The results show that the lytic effect of the phytotherapeuticum on histamine-induced contraction represents additively the actions of the different components and corresponds to approx. 10 μM of papaverine. Spontaneous peristaltic motion was differently modulated by the various constituent extracts. The experiments with silibinin, glycyrrhicine, chelidonine, and protopine showed that the effects of the extracts were not comparable to those of the respective chemical constituents.