Tutin is a poisonous plant derivative found in New Zealand tutu plants (several species in the genus Coriaria). It acts as a potent antagonist of the glycine receptor, and has powerful convulsant effects. It is used in scientific research into the glycine receptor. It is sometimes associated with outbreaks of toxic honey poisoning when bees feed on honeydew exudate from the sap-sucking passionvine hopper (Scolypopa australis) insect, when the vine hoppers have been feeding on the sap of tutu bushes. Toxic honey is a rare event and is more likely to occur when comb honey is eaten directly from a hive that has been harvesting honeydew from passionvine hoppers feeding on tutu plants.
^Fuentealba J, Guzmán L, Manríquez-Navarro P, Pérez C, Silva M, Becerra J, Aguayo LG (March 2007). "Inhibitory effects of tutin on glycine receptors in spinal neurons". European Journal of Pharmacology. 559 (1): 61–4. doi:10.1016/j.ejphar.2006.12.018. PMID17303114.