Antispasmodic effect of a herbal preparation on small intestine: Potential therapeutic benefits for IBS patients

Amara-Drops contains nine individual herbal extracts and is traditionally used to treat gastrointestinal dysmotility. It has been shown that the extract of Amara-Drops (Amara extract) targets the muscarinic receptor M2, inducing relaxation of carbachol-contracted guinea pig fundus strips, potentially improving impaired fundus accommodation in functional dyspepsia patients [ 1 ]. However, its antispasmodic properties to improve visceral hypersensitivity, a major factor in abdominal pain experienced by Irritable Bowel Syndrome (IBS) patients, have yet to be studied. While anticholinergic agents are commonly used to treat IBS, they often have broad side effects. Herbal medicines have demonstrated excellent antispasmodic properties without significant adverse reactions [ 2 ]. Therefore, we investigated the antispasmodic effect of Amara extract on guinea pig small intestine with or without carbachol-induced contraction. Ileum muscle strips were prepared and set up in organ baths in a longitudinal orientation. Exposure of Amara extract (94.4-1,000 μg/mL) to muscle strips induced significant relaxation at 450 μg/mL (25%, p