Catharnthus roseus is an evergreen subshrub or herbaceous plant growing 1 m (39 in) tall. The leaves are oval to oblong, 2.5–9 cm (1.0–3.5 in) long and 1–3.5 cm (0.4–1.4 in) broad, glossy green, hairless, with a pale midrib and a short petiole 1–1.8 cm (0.4–0.7 in) long; they are arranged in opposite pairs. The flowers are white to dark pink with a darker red centre, with a basal tube 2.5–3 cm (1.0–1.2 in) long and a corolla 2–5 cm (0.8–2.0 in) diameter with five petal-like lobes. The fruit is a pair of follicles 2–4 cm (0.8–1.6 in) long and 3 mm (0.1 in) broad

The species has long been cultivated for herbal medicine and as an ornamental plant. In the UK it has gained the Royal Horticultural Society’s Award of Garden Merit(confirmed 2017). In Ayurveda (Indian traditional medicine) the extracts of its roots and shoots, though poisonous, are used against several diseases. In traditional Chinese medicine, extracts from it have been used against numerous diseases, including diabetes, malaria, and Hodgkin’s lymphoma.Many of the vinca alkaloids were first isolated from Catharanthus roseus,including vinblastine and vincristine used in the treatment of leukemia and Hodgkin’s lymphoma.

Sources:
https://en.wikipedia.org/wiki/Catharanthus_roseus
https://medthai.com/แพงพวย/