Pyrrolizidine alkaloid-containing toxic plants (Senecio, Crotalaria, Cynoglossum, Amsinckia, Heliotropium, and Echium spp.).

Pyrrolizidine alkaloid (PA)-containing plants are found throughout the world and are probably the most common plant cause of poisoning of livestock, wildlife, and humans. PAs are potent liver toxins that under some conditions can be carcinogenic. This article briefly introduces high-risk North American PA-containing plants, summarizing their toxicity and subsequent pathology. Current diagnostic techniques, treatments, and strategies to avoid losses to PA poisoning are also reviewed.