It has naturalized throughout the world, and is considered an invasive weed in Africa, Australia, the southern United States, Hawaiian Islands, New Guinea, and French Polynesia.

[4][6] Sida cordifolia is an erect perennial that reaches 50 to 200 cm (20 to 79 in) tall, with the entire plant covered with soft white felt-like hair that is responsible for one of its common names, "flannel weed".

[4] As a weed, it invades cultivated and overgrazed fields, competing with more desired species and contaminating hay.

[16] The following alkaloids were reported from S. cordifolia growing in India:[17] β-phenethylamine, ephedrine, pseudoephedrine, S-(+)-Nb-methyltryptophan methyl ester, hypaphorine, vasicinone, vasicinol, choline, and betaine.

Recent analyses have revealed that ephedrine and pseudoephedrine constitute the major alkaloids from the aerial parts of the plant, which also show traces of sitosterol and palmitic, stearic and hexacosanoic acids.