Gravel root (Eupatorium purpureum), also known as Joe-Pye weed, has a long history of traditional use in North American herbal medicine for supporting the bladder and urinary system. Indigenous peoples and later European settlers employed gravel root as a diuretic and for the treatment of urinary tract ailments, including bladder infections, kidney stones, and difficulties with urination. The name "gravel root" itself is derived from its purported ability to help expel "gravel" (small stones) from the urinary tract.

The traditional rationale for its use centers on its diuretic action, promoting increased urine flow, which was believed to help flush out the bladder and kidneys. Herbalists have used it to address symptoms such as painful urination, urinary retention, and edema associated with urinary tract issues. Some herbal compendia and older materia medica texts list gravel root as a "bladder tonic."

However, there is a lack of modern scientific studies validating these traditional claims. Contemporary research on gravel root is limited, and its active compounds have not been conclusively shown to benefit the bladder in controlled clinical trials. Thus, while historical and traditional evidence for its use in bladder health exists, scientific support is currently lacking.