Euphorbia peplus

Not to be confused with Euphorbia peplis, Purple spurge, a relatively rare plant of coastal sand and shingle.

For other uses of "milkweed", see milkweed (disambiguation).

Euphorbia peplus
File:E peplus.jpg
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Malpighiales
Family:	Euphorbiaceae
Genus:	Euphorbia
Species:	E. peplus
Binomial name
Euphorbia peplus L.

Euphorbia peplus (petty spurge, radium weed, cancer weed, or milkweed) is a species of Euphorbia, native to most of Europe, northern Africa, and western Asia, where it typically grows in cultivated arable land, gardens, and other disturbed land.

Outside of its native range it is very widely naturalised and often invasive, including in Australia, New Zealand, North America, and other countries in temperate and sub-tropical regions.

Description

It is an annual plant growing to between 5–30 cm tall (most plants growing as weeds of cultivation tend towards the smaller end), with smooth hairless stems. The leaves are oval-acute, 1–3 cm long, with a smooth margin. It has green flowers in three-rayed umbels. The glands, typical of the Euphorbiaceae, are kidney-shaped with long thin horns.

Medicinal uses

The plant's sap is toxic to rapidly replicating human tissue, and has long been used as a traditional remedy for common skin lesions, including cancer. The active ingredient in the sap is a diterpene ester called ingenol mebutate. A pharmaceutical-grade ingenol mebutate gel has approval from the US Food and Drug Administration for treatment of actinic keratosis.