The rhizome is anti-fungal, antiseptic, bitter, diuretic, expectorant, febrifuge, hypoglycaemic, laxative, lenitive, sedative and tonic It has an antibacterial action, inhibiting the growth of Bacillus dysenteriae, B. typhi, B. paratyphi, Proteus and Pseudomonas. It is taken internally in the treatment of high fevers in infectious diseases, TB, chronic bronchitis, diabetes and urinary problems. It should not be given to patients with diarrhoea and should be administered with caution since when taken in excess it can cause a sudden drop in blood pressure. Externally, it is used as a mouthwash in the treatment of ulcers. The rhizome is harvested in the autumn and dried for later use.