Tabernanthalog and other ibogaine analogs: can they work without the long experience?

Ibogaine analogs are lab-made relatives of ibogaine. Chemists design them to keep its effect on drug use while dropping its long visionary state and its strain on the heart [1][2]. In rodent studies, tabernanthalog and 18-MC cut drug taking without ibogaine's main side effects [1][2]. The analogs are at the animal and early human safety stage [3].

What are ibogaine analogs?

Ibogaine analogs are compounds built on ibogaine's chemical frame and changed on purpose [4]. The relative with the most human data is noribogaine, the compound the body makes from ibogaine [5][6][7].

Three lines of engineered analogs have been tested in animals for effects on drug use. 18-MC came first. In rat studies from the 1990s, it reduced the use of several drugs [2][8].

Tabernanthalog, or TBG, followed in 2021, with results in mice and rats [1]. Oxa-iboga compounds appeared in 2024, tested in rats and in human heart cells grown in a dish [9].

18-MC has reached people. A safety trial in healthy volunteers finished in 2021, at a site in Perth, Australia [3]. It tracked side effects and how the body handles the drug [3].

People following ibogaine research often want to know whether a gentler version is close. Each candidate sits at a different stage. For the wider evidence on ibogaine itself, see Ibogaine: What the Evidence Shows in 2026.

Why do chemists redesign ibogaine?

Chemists redesign ibogaine because of what it does to the heart and how long it lasts [1]. In a Dutch hospital study of people with opioid dependence, the heart's QT interval passed 500 milliseconds in half the patients after one dose [10]. That interval is the heart's electrical reset between beats. In more than four in ten, it was still long a day later [10]. Every patient also lost their balance for a while and could not walk unaided [10].

In the same patients, noribogaine levels stayed far lower than in trials that gave it directly [11]. The QT rise and the unsteadiness tracked ibogaine levels instead [11]. By the team's estimate, a dose more than ten times smaller would be needed to cut the QT risk in a meaningful way [11].

The visionary state is long too. A St Kitts treatment team reported that people who process ibogaine slowly had a very strong experience lasting up to 24 hours [5]. Two people who cleared it very fast had ibogaine levels too low to measure. They reported no dream-like state at all [5].

Lab work shows where part of the heart risk comes from. In cell tests, ibogaine blocks hERG, a potassium channel the heart needs to reset each beat [12].

The design method works like testing a recipe. A cook drops one ingredient at a time to learn which ones carry the flavour. The TBG team built simpler versions of ibogaine, each missing part of its ring structure [1]. They then tested which versions still made rat brain cells grow new branches [1].

One piece of the molecule carried that effect. It was ibogaine's indole ring fused to a seven-membered ring [1]. Keeping that piece and dropping the rest gave compounds that chemists can make in a single step [1].

Do ibogaine analogs reduce drug use without the long experience?

In people, the closest relative with trial data is noribogaine, and it lengthens the heart's QT interval [6][13]. In rodent studies, 18-MC and TBG both reduced drug use without ibogaine's main side effects [1][2].

Given alone to people coming off methadone, noribogaine lengthened the QT interval more at each higher dose [6]. At the top dose, the largest average rise was about 42 milliseconds [6].

In a 2024 trial, healthy volunteers took it in repeated doses [13]. The trial recorded no serious adverse events [13]. Reported side effects included nausea, headache and feeling faint [13]. QT prolongation appeared as a side effect, more often at higher doses [13]. It showed up in most people on the top dose and in none on placebo [13].

In rats, 18-MC reduced the self-administration of morphine, cocaine, alcohol and nicotine [2]. Rat studies found it free of ibogaine's tremor, cerebellar damage and heart slowing [2].

In mice, TBG did not cause the head twitch that researchers use as a stand-in for hallucinations [1]. In cell tests, it blocked the hERG channel about a hundred times more weakly than ibogaine [1]. In mice that binge on alcohol, one dose cut drinking and left their taste for sugar water intact [1].

In rats, oxa-iboga compounds reduced morphine, heroin and fentanyl intake [9]. In human heart cells grown in the lab, they did not show ibogaine's rhythm-disturbing effects [9].

Do the analogs work the same way ibogaine does?

Lab and animal studies show each analog keeping a different part of ibogaine's action. Ibogaine binds many brain targets at once [16]. Picture it as a master key that turns many locks. Each analog is cut to fit one or two of them.

In lab studies, 18-MC's strongest action is blocking one nicotinic receptor, called alpha3beta4 [17].

In cell and mouse studies, TBG works through a serotonin receptor, 5-HT2A, the one classic psychedelics use [1]. In living mice, it added new dendritic spines, the small contact points between neurons [1].

In lab tests, the oxa-iboga compounds act on the kappa opioid receptor [9]. The full map of candidate targets is in How Ibogaine Interrupts Opioid Withdrawal: Candidate Mechanisms.

Noribogaine has been tested for this kind of action in people. In healthy men given small single doses, it showed no sign of acting like morphine or heroin [7]. Pupil size and pain tolerance, two standard tests for that kind of opioid action, stayed unchanged [7].

How long do the analogs last, and how are they made?

Noribogaine, the relative measured in people, stays in the body for days. Its half-life ran 24 to 30 hours in people coming off methadone [6]. In healthy volunteers given small single doses, it ran 28 to 49 hours [7]. Blood levels in that trial peaked 2 to 3 hours after the dose [7].

With repeated doses, it builds up. In the 2024 volunteer trial, peak blood levels on day 8 ran about two to three times those on day 1 [13]. The kinetics are covered in Noribogaine: Pharmacokinetics of the Long Tail.

18-MC depends on a different liver enzyme. In human liver tissue tested in the lab, CYP2C19 did most of the work of breaking it down [18]. The activity of that enzyme varies with a person's genes [18]. Ibogaine relies on another enzyme, CYP2D6 [5]. In St Kitts, most ibogaine had left the blood within a day, while noribogaine levels stayed high at 24 hours [5].

In rats, a single dose of TBG reduced cue-triggered heroin relapse for up to two weeks [1].

Supply is part of the design. TBG dissolves readily in salt water, unlike ibogaine [1].

Ibogaine makes up about 0.3% of iboga root bark [4]. Most ibogaine is made from voacangine, a related compound from the bark of the Voacanga africana tree [4][19].

Harvesting the plant has a cost. Overharvesting of iboga harms the cultures that use it in spiritual practice [19]. Among them is the Bwiti tradition of Gabon and Cameroon, where iboga is central [20].

A new route avoids the plant altogether. In 2025, chemists reported a seven-step synthesis of ibogaine from pyridine, a cheap and widely available chemical [19]. It works at gram scale [19]. The team notes that such a route could ease concerns about ecological sustainability [19]. The same route produced new analogs for testing [19]. More on ibogaine's own targets and kinetics is in The Pharmacology of Ibogaine: Targets, Kinetics, Metabolism.

What is the ibogaine experience that analogs try to remove?

Ibogaine treatment usually moves through two stages. A vivid, dream-like stage comes first, then a calm, thoughtful one [5][21]. In St Kitts, the visions began about 30 to 45 minutes after the dose [5]. The dream-like stage lasted 4 to 8 hours [5].

In that first stage, people see a stream of images. Many of them are memories of past events [21].

About four in ten people in St Kitts saw themselves as a child [5]. More than half felt linked to a higher power or to something larger than themselves [5].

The second stage is quieter. Attention turns to making sense of what came up [5][21]. This stage lasts roughly 8 to 20 hours [21]. Sleep is often hard for up to three days afterwards [21].

In a Dutch hospital study, patients described visions with their eyes closed and vivid memories [10].

The body feels it too. Nausea, vomiting and unsteady walking were the most common side effects in St Kitts [5]. About one person in twenty had a drop in blood pressure on standing up [5].

Noribogaine has also been given to patients on its own. In its first patient trial, the most common effects were changes in how light looked, headache and nausea [6]. Those light changes came about an hour after the dose [6]. In the 2024 repeated-dose trial, one person on the top dose had a spell of confusion [13].

Looking back, most people in St Kitts said they felt a benefit [5]. Nine in ten said it helped with their drug problem [5]. About one in six said they would go through it again [5]. A similar nine in ten said it gave them insight [5].

Researchers developing TBG note that many people credit psychedelic benefits to insights gained during the experience [22].

Where the research goes next

Four directions are open. The first is human data on an engineered analog. The 18-MC volunteer trial has finished [3]. Its safety and blood-level results are the next step.

The second is whether the visions matter. The TBG team suggests that some benefits might come without hallucinations [22]. A trial of a non-hallucinogenic analog in people with addiction would test that idea head on.

Third is heart checks built into every trial. Noribogaine, a close relative, still lengthened the QT interval in people [6][13].

The Dutch ibogaine study offers a model. It monitored each patient for at least a day. It gave magnesium once the QT interval passed 500 milliseconds [10].

The fourth question is which compound does the work. Given on its own to people coming off methadone, noribogaine gave a trend toward lower withdrawal scores that was not statistically significant [6].

For TBG, spine growth is linked to mood-related behaviour in mice [23]. Does the same growth drive its effect on drug seeking? That is still open [22]. The trials that could settle it are set out in Open Questions: What Rigorous Ibogaine Trials Must Answer.

Frequently asked questions

Has tabernanthalog been tested in humans?

Tabernanthalog's published results come from mice, rats, zebrafish and cells grown in the lab [1][15][23]. In those studies, it reduced alcohol drinking and heroin relapse [1].

What are the effects of tabernanthalog?

In lab and rodent studies, TBG acts on the 5-HT2A serotonin receptor [1]. It helps neurons grow new branches and spines [1]. In mice, it had an antidepressant-like effect a day after one dose [1].

How is noribogaine different from ibogaine?

Noribogaine is the compound the body makes from ibogaine, and it lasts much longer [5][6]. Ibogaine's half-life is about 1.6 to 6 hours [5]. Noribogaine's ran 24 to 30 hours in people coming off methadone [6]. Taken alone, it most often changed how light looked and caused headache and nausea [6]. It also lengthened the QT interval [6].

Is there a synthetic ibogaine?

Yes. In 2025, chemists reported a seven-step synthesis of ibogaine from pyridine, at gram scale [19]. Most ibogaine today is made from voacangine, a related compound taken from Voacanga africana bark [4][19].

Has noribogaine been tested in clinical trials?

Yes. Noribogaine has been given to people in three trials with reported results [6][7][13]. Healthy volunteers took small single doses in one and repeated daily doses in another [7][13]. In the third, people coming off methadone took single doses [6]. Their QT interval lengthened more at higher doses [6].