Acanthaceae

Andrographis paniculata

Andrographis · Kalmegh · King of bitters · Chuan xin lian

Trial support Caution

Part used: aerialleaf
Native range: India and Sri Lanka; cultivated across South and Southeast Asia
Morphology: An erect annual to a metre with slender four-angled stems, lance-shaped leaves and small white flowers marked with purple. Intensely bitter, which is what the English name records.

What is in it

diterpene lactones andrographolide, neoandrographolide

flavonoids

Evidence

Among the better-supported herbs for upper respiratory infection. Systematic reviews find it reduces symptom severity and duration of the common cold compared with placebo, with effects more consistent than echinacea. Trial quality is variable and many studies use a combination product with Eleutherococcus.

Safety

Gastrointestinal upset and rash are common. Anaphylaxis is reported. Male antifertility effects appear in animal studies and are unresolved in humans. Contraindicated in pregnancy — it has traditional abortifacient use.

Interactions: Additive with anticoagulants and antihypertensives; Immunostimulant; caution with immunosuppressants; May lower blood glucose

Regulatory: Permitted as a listed medicine ingredient in Australia. The TGA required an anaphylaxis warning after adverse event reports.

How the traditions classify it

Chinese Chuan xin lian — bitter and cold, for clearing heat and toxin.

Ayurvedic Kalmegh — bitter; cooling in potency. Used for fever and for the liver, and a principal ingredient of some classical liver formulations.

Three systems, rating the same plant. Where they disagree, none of them is correcting the others — they are separate frameworks that arrived at their categories independently.

Historical use

Used across South and Southeast Asia for fever and infection. Credited in Indian accounts with a role in managing the 1919 influenza epidemic, though the evidence for that is anecdotal.

Recorded as history and attributed where possible. Long use establishes that a plant was widely used, not that it worked, and not that it was safe.

Worth knowing

Andrographis is the herb echinacea is usually assumed to be. For upper respiratory infection it has better and more consistent trial evidence than echinacea has ever produced, and it is far less well known in the English-speaking world.

Australia's TGA has an unusually direct relationship with it. After a cluster of adverse event reports — including anaphylaxis and loss of taste — the regulator required specific warning statements on andrographis products, which is one of the few times an Australian regulator has acted on a single herb in that way.

That combination is instructive: it is one of the better-evidenced herbs here and one of the few that triggered a formal regulatory response. Working and being harmless are separate properties.

Nomenclature verified against GBIF backbone taxonomy.