Vinca rosea, also known as Catharanthus roseus, is a subtropical ornamental plant used in traditional medicine for treating various ailments, including diabetes and asthma, and contains alkaloids with anti-tumor properties. Datura metal, or stramonium, contains toxic tropane alkaloids and has a history of medicinal use for conditions like asthma and heart disorders, despite potential side effects. Both plants are utilized in herbal remedies across different cultures but require careful usage due to their toxic characteristics.