An erect much branched, gregarious, evergreen shrub, up to 2 (-2.5) m. Stem ± quadrangular to nearly terete, young shoots greyish-pubescent Leaves with (1-) 1.5-3.5 (-4.5) cm long petioles; lamina elliptic-lanceolate, 10-20 x 3.5-8 cm, glabrous above, pubescent on nerves beneath, basally attenuate, entire, acuinate. Flowers white, c. 3 cm long, nearly sessile, in terminal and axillary spikes, up to 10 cm long, 2.5-3 cm broad; bracts leafy, broadly-elliptic, 1.5-2.5 x (0.8) 1-1.5 (-1.8) cm, pubescent; bracteoles elliptic-oblong to lanceolate, 1-1.5 (-2) x 0.3-0.5 cm, acute, minutely pubescent. Calyx 5-lobed, lobes linear-lanceolate, 6-10 x c. 2 mm, acute, puberulous, imbricate. Corolla pale-white, tube 1.2-1.5 cm long, pubescent outside, throat villous, limb 2-lipped, upper lip erect, shortly bifid, galeate, lower lip with 3 elliptic, obtuse lobes. Stamens 2, filaments 1-1.5 cm long, anthers oblong, basally apiculate. Ovary oblong, c. 3 mm long, style 2-2.5 cm long. Capsule stipitate, broadly clavate, c. 2.5 cm long, 4-seeded, pubescent. Seeds ± orbicular, 2-3 mm across, glabrous.

Fl. Per.: November-April (plains); July-October (hills).

Type: ‘Habitat in Zeylona’, Herb. Linn. 28/1 (LINN).

Distribution: Panama (probably) introduced), Indonesia, Malaya, S.E. Asia, India and Pakistan.

In Pakistan, it does well on waste lands up to 1300 m; it is also cultivated as an ornamental.

Widely used in the Ayurvedic and Unani system of medicine for treating bronchitis, asthma, fever and jaundice on account of the antispasmodic properties of roots and leaves. The leaves contain an alkaloid vasicine and an essential oil.