CAMPANULACEAE

The Campanulaceae or bell-flower family comprises of some 2000+ species of herbaceous plants or shrubs with cosmopolitan distribution. They have showy flowers and fruits which are capsules containing numerous seeds. Many species also exude a white sap from their body. The subfamily Lobelioideae, which includes Lobelia spp., Hippobroma longiflora and Isotoma spp. elaborates a neurotoxic piperidine alkaloid called lobeline. Lobeline is somewhat similar to nicotine, it is a mild stimulant that causes lethal paralysis in overdose. Lobeline containing plants like the Indian tobacco (Lobelia inflata) and Devil’s tobacco (Lobelia tupa) are smoked as tobacco substitute. Lobeline was previously used as an anti-asthmatic drug, it was also marketed as nicotine replacement therapy. Recently, lobeline is shown to reverse addiction caused by drugs of abuse. It is an old drug that comes in and out of ‘fashion’. 

 

Star of Bethlehem (Hippobroma longiflora)

Hippobroma longiflora is infamous. It exudes a toxic white latex that is said to cause blindness on contact with the eyes. Ingestion of the plant can cause severe illness. H. longiflora is rich in lobeline and related alkaloids. However, there are no scientific evidence to support the exaggerated toxicity of this plant. 

Coin-leaf Lobelia (Lobelia nummularia)

Lobelia nummularia is a herbaceous creeper native to South Asia. It occurs in the montane forests of Malaysia. This species produces conspicuous fruit capsules that are bright purple in colour. Little is known about its toxicity.