Tabernanthine is an alkaloid found in Tabernanthe iboga. It has been used in laboratory experiments to study how addiction affects the brain. Tabernanthine persistently reduced the self-administration of cocaine and morphine in rats.
It is kappa opioid agonist (K<sub>i</sub> = 0.15 üM) and NMDA receptor (K<sub>i</sub> = 10.5 üM) antagonist. Compared to ibogaine, it binds weakly to ÃÂ<sub>1</sub> and ÃÂ<sub>2</sub> receptors.