Description

Asthma Weed is a pantropical weed, originating from the tropical regions of the Americas. It is a hairy herb that grows in open grasslands, roadsides and pathways in the warmer regions of India and Australia as an introduced species. It is used in traditional herbal medicine. Asthma Weed is a slender-stemmed, annual hairy plant with many branches, growing up to 40 cms tall, reddish or purplish in color. Leaves are opposite, elliptic-oblong to oblong-lancelike, 1-2.5 cm long, blotched with purple in the middle, toothed at the edge. Flowers, purplish to greenish in color, dense, axillary, short-stalked clusters or crowded cymes, about 1 mm in length. Capsules are broadly ovoid, hairy, three-angled, about 1.5 cm.

Characteristics:

Slender, erect, pubescent herbs about 20-35 cm tall. Leaves decussate, 1-2.5 x 0.7-1.5 cm, broadly oblong to elliptic-lanceolate, base obliquely truncate, margin serrulate, apex acute, hispid on both sides, basally 3-nerved; petiole to 3 mm long. Cyathia aggregated in single or paired axillary clusters. Involucre minute, c. 1 mm long; glands 5, red. Male flowers 4-6, ebracteolate. Female florets laterally pendulous; styles 2-fid from base. Capsule 1.5-2 mm across, pubescent. Seeds minute, red, 4-angled, minutely furrowed.

Medicinal Use:

Asthma weed has traditionally been used in Asia to treat bronchitic asthma and laryngeal spasm, though in modern herbalism it is more used in the treatment of intestinal amoebic dysentery. It should not be used without expert guidance, however, since large doses cause gastro-intestinal irritation, nausea and vomiting.