Main targets of ibogaine and noribogaine associated with its putative anti-addictive effects: A mechanistic overview.

BACKGROUND: There is a growing interest in studying ibogaine (IBO) as a potential treatment for substance use disorders (SUDs). However, its clinical use has been hindered for mainly two reasons: First, the lack of randomized, controlled studies informing about its safety and efficacy. And second, IBO's mechanisms of action remain obscure. It has been challenging to elucidate a predominant mechanism of action responsible for its anti-addictive effects. OBJECTIVE: To describe the main targets of IBO and its main metabolite, noribogaine (NOR), in relation to their putative anti-addictive effects, reviewing the updated literature available. METHODS: A comprehensive search involving MEDLINE and Google Scholar was undertaken, selecting papers published until July 2022. The inclusion criteria were both theoretical and experimental studies about the pharmacology of IBO. Additional publications were identified in the references of the initial papers. RESULTS: IBO and its main metabolite, NOR, can modulate several targets associated with SUDs. Instead of identifying key targets, the action of IBO should be understood as a complex modulation of multiple receptor systems, leading to potential synergies. The elucidation of IBO's pharmacology could be enhanced through the application of methodologies rooted in the polypharmacology paradigm. Such approaches possess the capability to describe multifaceted patterns within multi-target drugs. CONCLUSION: IBO displays complex effects through multiple targets. The information detailed here should guide future research on both mechanistic and therapeutic studies.

Ibogaína: un psicodélico atípico con potencial antiadictivo / Ibogaine: an atypical psychedelic with anti-addictive potential

El trastorno por uso de sustancias es una enfermedad crónica de graves consecuencias. Actualmente, los tratamientos farmacológicos no apuntan a corregir los cambios neurobiológicos generados en el cerebro por el uso crónico de sustancias de abuso, sino que se enfocan principalmente en la atenuación de algunos de los síntomas que padece el consumidor. La ibogaína es un psicodélico atípico que, tanto en estudios observacionales como en ensayos clínicos abiertos, ha mostrado una propiedad antiadictiva que perdura en el tiempo. Sin embargo, su delicado perfil de toxicidad cardíaca, así como su uso en entornos sin adecuadas medidas de seguridad, han limitado su progresión en las investigaciones clínicas. Los efectos antiadictivos de ibogaína han disparado diversas líneas de investigación básica, preclínica y clínica, que buscan confirmar su efectividad, entender sus mecanismos de acción y delimitar su perfil de seguridad. Dada la poca información disponible para los profesionales de salud sobre esta sustancia, esta revisión busca aportar información acerca de su potencial terapéutico, posibles mecanismos de acción y riesgos asociados a su administración.

Substance use disorder is a chronic disease with severe consequences. Currently, pharmacological treatments do not aim to correct the neurobiological changes generated in the brain by the chronic use of substances of abuse, but rather focus mainly on attenuating some of the user's symptoms. Ibogaine is an atypical psychedelic that has shown long-lasting and interesting antiaddictive properties in both observational studies and open-label clinical trials. However, its delicate profile of cardiac toxicity, as well as its use in settings without adequate safety measures, have limited its progression in clinical research. The anti-addictive effects of ibogaine have triggered diverse scientific research in basic, preclinical, and clinical areas, which seek efficacy confirmation and to fully understand ibogaine´s underlying mechanisms of action and its safety profile. Given that there is little information available to health professionals about ibogaine and its antiaddictive properties, this review aims to provide published data about its therapeutic potential in drug addiction, its mechanisms of action, and risks associated with its administration.

A non-hallucinogenic psychedelic analogue with therapeutic potential.

The psychedelic alkaloid ibogaine has anti-addictive properties in both humans and animals1. Unlike most medications for the treatment of substance use disorders, anecdotal reports suggest that ibogaine has the potential to treat addiction to various substances, including opiates, alcohol and psychostimulants. The effects of ibogaine-like those of other psychedelic compounds-are long-lasting2, which has been attributed to its ability to modify addiction-related neural circuitry through the activation of neurotrophic factor signalling3,4. However, several safety concerns have hindered the clinical development of ibogaine, including its toxicity, hallucinogenic potential and tendency to induce cardiac arrhythmias. Here we apply the principles of function-oriented synthesis to identify the key structural elements of the potential therapeutic pharmacophore of ibogaine, and we use this information to engineer tabernanthalog-a water-soluble, non-hallucinogenic, non-toxic analogue of ibogaine that can be prepared in a single step. In rodents, tabernanthalog was found to promote structural neural plasticity, reduce alcohol- and heroin-seeking behaviour, and produce antidepressant-like effects. This work demonstrates that, through careful chemical design, it is possible to modify a psychedelic compound to produce a safer, non-hallucinogenic variant that has therapeutic potential.

Ibogaine Consumption With Seizure-Like Episodes, QTc-Prolongation, and Captured Cardiac Dysrhythmias.

BACKGROUND: Ibogaine is a psychoactive indole alkaloid that has been investigated for use as a treatment for opioid addiction. While not commercially available in the United States, it is available via Internet suppliers. Ibogaine use has been associated with significant cardiac and neurologic effects, such as QT-segment prolongation, cardiac dysrhythmias, hallucinations, seizures, and central nervous system depression. We present a case of verified ibogaine exposure with associated QTc prolongation and torsade de pointes with qualitative analysis of the ingested substance, and examine the history, social context, availability, and perceptions of ibogaine's effects and safety. CASE REPORT: A 34-year-old white woman with medical history significant for heroin and cocaine use disorder presented with reported seizures 1 day after ingestion of 2 g ibogaine powder purchased from an Internet supplier. Shortly after ingestion, she experienced hallucinations and was reported by family to have four to five seizure-like episodes, at one point becoming apneic. In the emergency department, she was noted to have QTc prolongation and several episodes of torsade de pointes. Qualitative analysis confirmed the presence of ibogaine in the empty foil packages containing the ingested substance. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: As increasing numbers of opioid-dependent patients attempt to curtail their substance use disorders, we anticipate a rise in ibogaine exposures, necessitating awareness by front-line clinicians in recognizing and treating a drug exposure that can rapidly become life-threatening.

Mechanism of hERG channel block by the psychoactive indole alkaloid ibogaine.

Ibogaine is a psychoactive indole alkaloid. Its use as an antiaddictive agent has been accompanied by QT prolongation and cardiac arrhythmias, which are most likely caused by human ether a go-go-related gene (hERG) potassium channel inhibition. Therefore, we studied in detail the interaction of ibogaine with hERG channels heterologously expressed in mammalian kidney tsA-201 cells. Currents through hERG channels were blocked regardless of whether ibogaine was applied via the extracellular or intracellular solution. The extent of inhibition was determined by the relative pH values. Block occurred during activation of the channels and was not observed for resting channels. With increasing depolarizations, ibogaine block grew and developed faster. Steady-state activation and inactivation of the channel were shifted to more negative potentials. Deactivation was slowed, whereas inactivation was accelerated. Mutations in the binding site reported for other hERG channel blockers (Y652A and F656A) reduced the potency of ibogaine, whereas an inactivation-deficient double mutant (G628C/S631C) was as sensitive as wild-type channels. Molecular drug docking indicated binding within the inner cavity of the channel independently of the protonation of ibogaine. Experimental current traces were fit to a kinetic model of hERG channel gating, revealing preferential binding of ibogaine to the open and inactivated state. Taken together, these findings show that ibogaine blocks hERG channels from the cytosolic side either in its charged form alone or in company with its uncharged form and alters the currents by changing the relative contribution of channel states over time.

Anti-addiction drug ibogaine inhibits hERG channels: a cardiac arrhythmia risk.

Ibogaine, an alkaloid derived from the African shrub Tabernanthe iboga, has shown promising anti-addictive properties in animals. Anecdotal evidence suggests that ibogaine is also anti-addictive in humans. Thus, it alleviates drug craving and impedes relapse of drug use. Although not licensed as therapeutic drug, and despite evidence that ibogaine may disturb the rhythm of the heart, this alkaloid is currently used as an anti-addiction drug in alternative medicine. Here, we report that therapeutic concentrations of ibogaine reduce currents through human ether-a-go-go-related gene potassium channels. Thereby, we provide a mechanism by which ibogaine may generate life-threatening cardiac arrhythmias.

Fatalities temporally associated with the ingestion of ibogaine.

Ibogaine is a naturally occurring psychoactive plant alkaloid that is used globally in medical and nonmedical settings for opioid detoxification and other substance use indications. All available autopsy, toxicological, and investigative reports were systematically reviewed for the consecutive series of all known fatalities outside of West Central Africa temporally related to the use of ibogaine from 1990 through 2008. Nineteen individuals (15 men, four women between 24 and 54 years old) are known to have died within 1.5-76 h of taking ibogaine. The clinical and postmortem evidence did not suggest a characteristic syndrome of neurotoxicity. Advanced preexisting medical comorbidities, which were mainly cardiovascular, and/or one or more commonly abused substances explained or contributed to the death in 12 of the 14 cases for which adequate postmortem data were available. Other apparent risk factors include seizures associated with withdrawal from alcohol and benzodiazepines and the uninformed use of ethnopharmacological forms of ibogaine.

A preliminary investigation of ibogaine: case reports and recommendations for further study.

A naturally occurring substance, ibogaine, was taken by seven individuals who were addicted to opiates. Ibogaine, an alkaloid with psychotropic effects at doses of 200-300 mg and above, was taken in single doses of 700-1800 mg by the subjects in the study. At the end of the 24-38-hr psychoactive period induced by the drug at these doses, none of the subjects displayed significant opiate withdrawal symptoms. At the lowest dose of 700 mg, one subject recontinued his drug abuse after 2 days; of the remaining six individuals who took 1,000 mg or above, two relapsed after a number of weeks, one reverted to intermittent heroin use, and three appear to have remained drug-free 14 weeks or more after undergoing this experimental treatment. Ibogaine may be of value in the present and could serve as a model for the development of improved agents for the treatment of substance abuse in the future.