Perennial herbaceous plant with a large vertical rhizome, with basal, ovate or elliptical leaves in outline, entire-extreme and acuminate at the apex, weakly heart-shaped or rounded at the base, turning into a long petiole. Stem up to 70 cm tall, leafless, obtusely trihedral, bearing a whorled panicle of pale pink flowers. Blooms all summer.
It grows in swamps, river banks, lakes, streams and ditches. The whole plant is a medicinal raw material in folk medicine. Rhizomes contain resin, tannins, essential oil. The fresh herb is a substance that irritates the skin and causes blistering.
In folk medicine, a decoction of rhizomes with roots or herbs is drunk when bitten by rabid animals; it is even better to eat raw rhizomes with roots for this purpose; a decoction of rhizomes with roots is used orally for venereal diseases; a decoction of the herb is taken for jaundice; fresh leaves are applied to boils.