Marsh Cudweed is an annual plant, 5-25 cm tall. The stem is raised, branches already in the lower part, fine and hairy with grayish-green hair. The leaves are arranged alternately, sessile, linear-lanceolate, up to 5 cm long and up to 3 cm wide, gray hairy, entire edge, with one vein. The flowers are brown-yellowish, small, arranged in egg-shaped baskets, which are densely located at the tops of the stems, 1-4 inflorescences each. Blooms in July-August. The fruits ripen from July.
For medical purposes, usually, only wild plants are harvested, when they bloom, July-August. When collecting the plant, pull it with all the roots, dry it in a shaded and well-ventilated place or in forced dryers, not exceeding the temperature of 40-50C.
Medicinal properties are provided by substances present in the plant: flavonoids (gnaphosides A and B, luteolin, scutellarein, scutellarein glycoside, rutin, tricin, eupafolin, quercitin), chlorogenic acid and caffeic acid, carotenoids (up to 55 mg/%), as well as vitamin C, thiamin, resins (<16%), tannins (<4%), coumarins, alkaloids (gnaphalin), essential oil (<0.05%), phytosterols.
Marsh Cudweed works as an anti-inflammatory, antibacterial, astringent, vasodilator, sedative and hypotensive agent, it also reduces the heart rate.
Plant preparations also enhance the processes of reparation, regeneration and epithelization. Marsh Cudweed can be used externally, making applications from it to treat trophic ulcers and burns. It can be used to rinse the uterus in case of uterine erosion.
An oil extract of this plant is particularly effective in treating hard-to-heal wounds and festering ulcers.
In folk medicine, this plant is additionally used as a decoction to treat gastric and duodenal ulcers, to reduce blood pressure, to treat tuberculosis, diabetes, intestinal diseases, angina pectoris. Externally to heal wounds. Oil extracts are used to enhance regeneration processes in case of ulcers and burns.