Traditional use: Native American peoples of the Pacific Northwest have used it for centuries as a gentle laxative; in the late 19th century, it was widely adopted into European and American pharmacy as one of the most prescribed botanical laxatives for chronic constipation. 

Potential benefits: Hydroxyanthracene glycosides (cascarosides) stimulate peristalsis and reduce colonic water reabsorption, producing a reliable, predictable laxative effect within 6–12 hours; considered one of the gentler stimulant laxatives with less griping than senna. 

Warnings: Fresh bark is toxic—it must be aged for at least 1 year or heat-cured; long-term use can cause electrolyte imbalance, potassium depletion, and laxative dependence; it is contraindicated in pregnancy, breastfeeding, bowel obstruction, and inflammatory bowel disease; limit use to 1–2 weeks.