Andrographis is a genus of approximately 26 species of flowering herbs and shrubs belonging to the family Acanthaceae, within the order Lamiales. The genus is sometimes collectively called "false waterwillows," a name that reflects a superficial resemblance to true waterwillows (genus Justicia), and several species are also known by the vernacular name periyanagai in South Asian languages.
The plants are native to the Indian subcontinent, with the core range spanning peninsular India, Sri Lanka, Myanmar, and the West Himalayan foothills. A large proportion of the species are endemic to India. Beyond their native range, several species have been introduced or are actively cultivated across Southeast Asia, and a smaller number have naturalized in parts of the Caribbean.
The most prominent member of the genus is Andrographis paniculata, commonly known as creat or green chiretta. This erect annual herb has a long history of use in Ayurvedic, Unani, and Siddha traditional medicine systems, where it is prescribed for a broad spectrum of conditions — particularly febrile illnesses, liver complaints, and gastrointestinal disorders. Its principal bioactive compounds, the labdane diterpenoids known as andrographolides, have attracted substantial pharmacological research interest.
Etymology
The genus name Andrographis derives from Greek roots: andros (man) and grapho (to write or mark), though the precise reasoning behind the combination as applied to this genus is not firmly established in available sources. The common name "false waterwillow" alludes to the plant's resemblance to members of the related genus Justicia.
Distribution
All species in the genus are native to the Indian subcontinent, with the center of diversity in peninsular India; many are endemic to India. The range also includes Sri Lanka, Myanmar, and the West Himalayan region. Andrographis paniculata has been widely introduced and is cultivated throughout Southeast Asia, and some populations exist in parts of the Caribbean. The genus is absent from the wild in Europe and the Americas.
Cultural Uses
Andrographis paniculata holds a prominent place in South and Southeast Asian traditional medicine. It is a key herb in Ayurveda, Unani, and Siddha systems, used to treat febrile illness, liver disease, respiratory infections, and intestinal complaints, earning it folk names such as "King of Bitters" in reference to its intensely bitter taste. A. alata and A. lineata are similarly employed in human and veterinary medicine in the region. Food uses of certain species have also been recorded, though medicinal application is the primary traditional use.
