Ibogaine is a psychoactive indole alkaloid derived from plants such as Tabernanthe iboga, characterized by hallucinogenic and oneirogenic effects. Ibogaine exhibits complex pharmacology by interacting with multiple neurotransmitter systems, notably affecting opioid, serotonin, sigma, NMDA, and nicotinic acetylcholine receptors; its metabolite noribogaine primarily acts as a serotonin reuptake inhibitor and κ-opioid receptor agonist.
The psychoactivity of the root bark of the iboga tree, T. iboga, one of the plants from which ibogaine is extracted, was first discovered by forager tribes in Central Africa, who passed the knowledge to the Bwiti tribe of Gabon. It was first documented in the 19th century for its spiritual use, later isolated and synthesized for its psychoactive properties, briefly marketed in Europe as a stimulant, and ultimately controversially researched for its potential in treating addiction despite being classified as a controlled substance. Ibogaine can be semisynthetically produced from voacangine, with its total synthesis achieved in 1956 and its structure confirmed by X-ray crystallography in 1960. Its clinical use and development have been limited due to regulatory barriers and serious safety risks, such as toxicity to the heart.
Ibogaine produces a two-phase experience—initially visionary and dream-like with vivid imagery and altered perception, followed by an introspective period marked by lingering side effects, such as nausea and mood disturbances, which may persist for days. Long-term risks include mania and heart issues such as long QT syndrome, and potentially fatal interactions with other drugs.
Only two randomized controlled trials have been conducted on ibogaine and noribogaine for substance use disorders, and while they show preliminary anti-addictive potential, their safety and efficacy are unconfirmed, with significant risks including cardiotoxicity and fatalities. Ibogaine is federally illegal in the United States. It is used in treatment clinics abroad under legal gray areas, with growing media attention. It has inspired the development of non-hallucinogenic, non-cardiotoxic analogues like 18-MC and tabernanthalog for therapeutic use. In 2025, Texas allocated $50 million for clinical research on ibogaine to develop FDA-approved treatments for opioid use disorder, co-occurring substance use disorders, and other ibogaine-responsive conditions. A 2026 US executive order directed federal agencies to accelerate review of ibogaine.
Use and effects
Ibogaine is derived from the root of Tabernanthe iboga, a plant known to exhibit hallucinogenic effects in people who consume it. It is described as having a typical dose range of 1,000 to 1,500mg orally, with these doses producing hallucinogenic effects, and a duration of 18 to 36hours. However, lower doses like 200 to 400mg orally are also active and said to be hallucinogenic. In addition, very low doses of ibogaine, like 8 to 50mg orally, have been used and reported to produce stimulant or "antidepressant" effects. The onset of the drug is 1 to 3hours and peak effects have been described as being reached after 2hours. With full hallucinogenic doses, ibogaine is described as having three different phases of effects. The first phase is the acute or visionary phase, which onsets after 1 to 3hours and has a duration of 4 to 8hours; the second phase is the evaluative or introspective phase, which starts after 4 to 8hours and has a duration of 8 to 20hours; and the third phase is residual stimulation, which onsets after 12 to 24hours and has a duration of 24 to 72hours or longer. Each of these phases is described as having distinct qualitative effects.
The visionary phase is a dream-like, conscious state called oneirophrenia. Visual effects are almost always present and are often described as films or slideshows. These may be accompanied by increases in long-term visual memory, resulting in autobiographical content. Other changes to sensation and perception may occur, including auditory hallucinations or distortions. Nausea and vomiting can be severe. Subjects may experience extreme confusion and/or a depressed mood. The visionary stage typically lasts 4–8 hours, but may last longer with especially high doses.
The introspective phase is poorly defined, often simply as 24 or 36 hours post-treatment. Sensation and perception return to normal, but nausea, headaches, and other side effects linger. Insomnia, irritability, and mood changes are often seen, including depression and sometimes mania. Depression can persist well after 36 hours, known as a "grey day"; the effect is well-recognized. A persistently low mood can progress into major depressive disorder, a chronic condition. For the treatment of opioid or alcohol addiction, the subjective experiences do not appear to be important, although they are correlated with some secondary measures (e.g., satisfaction in self-assessments).
Ibogaine has been referred to as an oneirogen (oneirophrenic or oneiric), or a hallucinogen that produces a dream-like state of consciousness.Naranjo, C. (1996). The Interpretation of Psychedelic Experience in Light of the Psychology of Meditation. Sacred Plants, Consciousness and Healing (pp. 75–90). https://www.claudionaranjo.net/pdf_files/psychedelics/psychedelics_and_meditation_english.pdf "Psychedelic substances differ in their psychological effects. I find it useful to classify them in three distinct groups: the LSD-like ones, which might also be called, in accordance with common usage "hallucinogens"; those like MDA (Methylene-dioxyamphetamine) and MMDA (Methoxy methylene-dioxy-amphetamine), which I proposed calling "feeling enhancers" (currently more referred to as entactogens); and the "fantasy enhancers" or oneirophrenics such as harmaline and ibogaine." This unique altered state of consciousness is shared with harmala alkaloids like harmaline but is distinct from that of other hallucinogens like serotonergic psychedelics such as LSD or psilocybin.
Contraindications Ibogaine should not be used during pregnancy or breastfeeding.
Adverse effects There is a need for controlled clinical trials before the safety of ibogaine can be established; existing evidence, largely from uncontrolled case reports, links it to significant acute and long-term adverse events (especially cardiac issues like QTc prolongation), including fatalities. It should only be used in medically supervised settings with thorough screening and continuous cardiac and psychiatric monitoring.
Ibogaine can cause various cardiovascular changes (e.g., slowed heart rate, blood pressure shifts), neurological effects (ataxia, tremor, mania), and rare but serious complications, including arrhythmias, respiratory failure, and death, especially when combined with opioids or in patients with underlying conditions.
Cardiac risks likely occur through hERG channel blockade leading to QT prolongation and arrhythmias; the synthetic analog 18-MC appears to produce much less of this dangerous effect despite similar binding affinity.
A 2022 review found 58ibogaine-associated emergencies, including 38deaths. Two of these deaths occurred in the setting of clinical studies. According to a 2012 estimate, 1 in every 300patients who take ibogaine die.
Neurotoxicity Laboratory studies in rats indicate that ibogaine at high doses may cause degeneration of Purkinje cells in the cerebellum. This also occurred with the related drug harmaline. However, subsequent research found no evidence of this neurotoxicity with ibogaine in a primate. In limited human research, neuropathological examination revealed no evidence of neuronal degenerative changes in an adult female patient who had received four separate doses of ibogaine ranging between 10 and 30 mg/kg over a 15-month interval. A published series of fatalities associated with ibogaine ingestion also found no evidence for consistent neurotoxicity.
Interactions Ibogaine has potential for adverse interactions with other psychedelic agents and prescription drugs. It may interact with monoamine oxidase inhibitors (MAOIs), for instance due to its serotonin reuptake inhibition.
Pharmacology Pharmacodynamics
+ Target Affinity (Ki, nM) Species 5-HT1A >10,000 (Ki) () Human/ratHuman 5-HT2A 12,500–16,000 (Ki) () RatHuman 5-HT2C >10,000 (Ki) () Rat/calfHuman 5-HT3 2,600–>10,000 (Ki) () Mouse/rat D1 >10,000 Human/calf M1 16,000–31,600 Calf/unspecified M2 31,000–50,100 Calf/unspecified M3 12,500 Unspecified 1,050–17,000 (Ki)220–5,000 () HumanUnspecified I2 σ1 2,500–9,310 Guinea pig/calf σ2 90–400 Rat/guinea pig/calf 6,920–11,040 (Ki) ()<5% () HumanHumanHuman 3,680–3,770 (Ki)~12,000 ()~18–21% () HumanHumanHuman NMDA () 1,010–9,800 Rat/bovine/human 549 (Ki)3,037–29,000 ()153,000 or () HumanHumanHuman (Ki)>100,000 () HumanBovine 1,980 (Ki)20,000 () () HumanRatRat 390–14,600 () Human 9,310 () Human 3,600–8,100 (Ki) Bovine/unspecified 28,000 () Unspecified 710 (Ki)3,530–4,090 () HumanHuman Notes: The smaller the value, the more avidly the drug binds to the site. All proteins are human unless otherwise specified. Refs:
Ibogaine affects many different neurotransmitter systems simultaneously and hence has complex pharmacology. The specific targets mediating the effects of ibogaine are not fully clear. The drug is a cyclized derivative of serotonin, and hence may be expected to have serotonergic actions, but shows relatively low affinity for serotonin receptors. In any case, it appears that the serotonin 5-HT2A, 5-HT2C, sigma σ2, and μ- and/or κ-opioid receptors may be involved in the subjective effects of ibogaine based on animal studies. Conversely, the NMDA, serotonin 5-HT1A and 5-HT3, and sigma σ1 receptors do not appear to be involved.
Ibogaine's major active metabolite noribogaine has similar discriminative stimulus properties compared to ibogaine in rodent drug discrimination tests, but only partially substitutes for ibogaine. It appears that the stimulus properties of ibogaine may be primarily mediated by noribogaine. Noribogaine is most potent as a serotonin reuptake inhibitor. It acts as a moderate κ-opioid receptor agonist and weak μ-opioid receptor agonist or weak partial agonist. The action of ibogaine at the κ-opioid receptor may indeed contribute significantly to the psychoactive effects attributed to ibogaine ingestion; Salvia divinorum, another plant recognized for its strong hallucinogenic properties, contains the chemical salvinorin A, which is a highly selective κ-opioid agonist. Noribogaine is more potent than ibogaine in rat drug discrimination assays when tested for the subjective effects of ibogaine.
There has been uncertainty about which biological target interactions mediate the psychoactive and other effects of ibogaine. Rodent drug discrimination studies with ibogaine have been employed to help elucidate these interactions. Ibogaine partially substitutes for the serotonergic psychedelics LSD and DOM and this can be blocked by the serotonin 5-HT2 receptor antagonist pizotifen. Similarly, LSD and DOM partially substitute for ibogaine and this can be blocked by the serotonin 5-HT2A receptor antagonist pirenperone. The serotonin releasing agent and potent serotonin 5-HT2 receptor agonist fenfluramine also partially substitutes for ibogaine. The preferential serotonin 5-HT2C receptor agonists MK-212 and mCPP partially substitute for ibogaine as well and this can be blocked by the serotonin 5-HT2 receptor antagonist metergoline. The preceding findings suggest that serotonin 5-HT2A and 5-HT2C receptor activation are involved in the subjective effects of ibogaine. Conversely, the serotonin 5-HT1A and 5-HT3 receptors do not appear to be involved.