Wild Indigo
What is it? Overview Usage Side Effects and Warnings

What is Wild Indigo?

Like its botanical relative true indigo ( Indigofera tinctoria), wild indigo has historically been used as a source of a deep blue dye. It was also used medicinally: the natives of North America used it as a topical treatment for non-healing wounds and infections of the mouth and throat. The root is the part used.

Currently, wild indigo is primarily used as part of a standardized four-herb combination said to improve immune function. This combination contains, besides wild indigo, Echinacea purpurearoot, Echinacea pallidaroot, and white cedar ( Thuja occididentalis). This combination is hypothesized to have immune-stimulating properties.

In a well-designed double-blind study of 263 people with recent onset of the common cold , use of this combination significantly improved cold symptoms as compared to placebo. 1 Recovery occurred approximately 3 days earlier among people taking the herbal mixture as compared to those taking the placebo.

Benefits for the common cold were also seen in other double-blind, placebo-controlled studies involving a total of about 250 people. 2 3 The...

Safety Issues

Wild indigo has not undergone comprehensive safety testing. However, in clinical studies, use of the standardized combination therapy has not been associated with any serious harmful effects. Safety in young children, pregnant or nursing women, or people with severe liver or kidney disease has not been established.