Ratanhia, also called rhatany or, more scientifically, Krameria, is a genus of shrub found in the semi-desert regions of the Americas, including Peru, Ecuador, Texas, Chile, Mexico, Bolivia, the West Indies, and northern Brazil. The plant has spindly, soft, white branches, red roots, and red or pink flowers with four or five petals. Ratanhia belongs to the family Krameriaceae and has several species within its genus, three of which are used in homeopathic remedies. Rhataniatannic acid, a natural astringent, can be extracted from the dried roots of Krameria argentea and Krameria lappacea, both referred to as para rhatany, and Krameria triandra, also called Peruvian ratanhia. The plant is used to control bleeding and treat sore throats and diarrhea.
Ratanhia generally grows to a height of roughly 25 cm (9.8 in), though this may vary between species. As a hemiparasitic plant, rhatany feeds off other host plants to obtain some of its sustenance. Krameria prefers to grow in arid climates on sunny plots of land, often at high altitudes. As they grow very slowly and are harvested for their medicinal qualities, ratanhia plants have been threatened in the past. Today, environmental groups have outlined methods for sustainable harvesting, such as planting new seeds for every plant harvested and reducing the amount of plants that can be dug up in a year.
Rhatany’s major value as a commercial good is due to krameric acid, a tannin found within the bark of the root. Tannins are a type of astringent, or substance that shrinks tissues, which constrict proteins. These chemicals are associated with the bitterness and dryness experienced when drinking some wines and teas. As this is often a sought after taste, Ratanhia has been exported, particularly to Portugal, to serve as an additive in wines.
In its medicinal uses, Ratanhia can be drunk, gargled, or applied topically as a tincture or syrup to shrink tissues throughout the body. People may drink the tincture in order to constrict tissues to restrict the flow of blood or secretions of mucous. This can be useful for patients with diarrhea or peptic ulcers, though these patients may need additional medical care in some cases. Ratanhia can also be gargled to help relieve sore throats by reducing mucous secretions. In its topical application, Krameria is often used to stem bleeding in small wounds, such as a pulled tooth or a tear in the anus.
Rhatany is typically prepared by drying the root and then extracting the tannic acid. The extraction is usually produced by steeping the dried bark root, often in powdered form, in alcohol or cold water. It can also be made by placing the bark in a container with boiling water and rapidly evaporating the water, leaving the extract. The Ratanhia extract can then be taken as a tincture or be mixed into a syrup, lozenge, or infusion.