Botanical Overview
Star-Thistle (Centaurea calcitrapa) belongs to the Asteraceae family. While not among the most extensively documented medicinal plants, this species has recorded uses that warrant attention from researchers and practitioners. The daisy family (Asteraceae) is one of the largest plant families, characterized by composite flower heads (capitula) that contain many small florets surrounded by bracts. Plants range from tiny alpine herbs to large tropical trees. The family includes many medicinally important species with bitter compounds and essential oils.

General Description
It is native to Europe but is known across the globe as an introduced species and often a noxious weed. The species name calcitrapa comes from the word caltrop, a type of weapon covered in sharp spikes.
Family Context
The Asteraceae family is extremely large and diverse. Notable medicinal members include:
- Yarrow — 63 documented uses
- Gobo — 63 documented uses
- Mugwort — 55 documented uses
- Sunflower — 52 documented uses
Geographic Distribution
Star-Thistle has been recorded in 10 countries and territories worldwide, including Australia, Germany, Spain, France, United Kingdom, and others.
Traditional Uses
Star-Thistle has been traditionally used for urinary tract health, fever management, and reproductive health, among other applications.
Urinary tract health.
- Diuretic
- Gravel
Urinary tract applications typically involve drinking the herb as a mild tea, which increases urine production and helps flush the urinary system. It may be combined with other demulcent herbs to soothe irritated tissues.
Fever management.
- Fever
Febrifuge preparations are typically administered as hot teas to induce perspiration, which helps the body regulate temperature. The patient is kept warm and encouraged to rest while the herb promotes sweating.
Reproductive health.
- Emmenagogue
In traditional contexts, reproductive health applications typically involve internal preparations such as teas or decoctions. The herb may be taken at specific times during the menstrual cycle.
Active Compounds
Phytochemical research has identified 26 compounds in this species, including a diverse array of phytochemical classes (see the Complete Chemical Inventory below for the full list).
The identified compounds include the following categories:
- Sterol: cholesterol-like compounds with anti-inflammatory properties
- Alkaloid: nitrogenous compounds with diverse pharmacological activities