View photos of the medicinal plant Iris missouriensis (Wild iris), profiled in Medicinal Plants of the Western Mountain States.

A passage from Medicinal Plants of the Western Mountain States:

As a visceral organ enlivener the plant is significant. Its action is two–fold: superficially it stimulates the gastrointestinal tissues via topical contact, but more profoundly, Wild iris increases both pancreatic and hepatic secretions. This combination makes the plant specific for individuals suffering from poor fat digestion/assimilation with general nutrient malabsorption. Candidates for Wild iris are plagued by frontal headache, nausea, and even skin rashes after rich and fatty meals. Dietary–related liver/gallbladder tenderness, area fullness, and sporadic clay/light–colored stools are a number of other related symptoms that indicate its use.