Comparing Amounts Administered In Tianeptine Research Studies

Written By: Neat Digital, Research Content Writer

Reviewed By: Natalie Kunsman, M.D., Board-Certified Physician

Last Reviewed: September 14, 2026

Published tianeptine research studies do not agree on how much tianeptine to administer, and the gap is wider than it looks. Cell-based receptor work uses concentrations in the nanomolar to micromolar range. Animal studies inject amounts from 0.25 to 10 mg per kilogram. Those numbers are not directly comparable, because three things change what a stated amount actually delivers: the salt form on the label, the route it goes in by, and the species it goes into. This article compares amounts administered across tianeptine research studies and shows how to line them up correctly, using verified molecular data and the published pharmacology. Tianeptine is sold strictly for laboratory research and educational use, not for human consumption. One fact frames all of it: on July 8, 2026, the DEA proposed placing tianeptine in Schedule I.

Tianeptine is a research material studied as a full mu-opioid receptor agonist. In the literature it appears as three salt forms: the free acid (436.95 g/mol), the sodium salt (458.9 g/mol), and a sulfate salt that is heavier again. Each form puts a different molar amount of the tianeptine cation into the same stated mass, which is where cross-study comparison starts to break.

Identity data drawn from PubChem. Salt stoichiometry varies by supplier; some list a hemisulfate (CAS 1224690-84-9), so confirm the exact form on the certificate of analysis before you convert anything. The tianeptine free acid, the sodium salt, and the sulfate are all sold as tianeptine research materials, for laboratory research and educational use only, not for human consumption.

Reported Tianeptine Amounts Differ For Three Reasons

Three variables move the number: salt form, route, and species. Miss any one of them and a comparison between two studies is comparing labels, not exposures. Everything below is a worked version of these three.

Salt form changes the mass. Route changes how much of that mass reaches the target and how fast. Species changes how the target responds to what arrives. A fourth factor sits under all of them, purity, because a stated mass only means something if the material is what the label claims. Front-load these four and the rest of the comparison becomes arithmetic instead of guesswork.

What Tianeptine's Mu-Opioid Mechanism Means For Study Design

Tianeptine's research design starts with its target, and the target is not what the field assumed for two decades. Gassaway and colleagues, reporting in 2014 in Translational Psychiatry, found tianeptine is a full agonist at the mu-opioid receptor with no appreciable activity at monoamine transporters, glutamate receptors, or the kappa-opioid receptor. The older description of tianeptine as a serotonin reuptake enhancer does not hold, which matters when you read a study designed around the wrong mechanism.

The binding and functional numbers set the scale for every in-vitro study that follows. At the human mu-opioid receptor, tianeptine showed a binding affinity (Ki) near 383 nM and a functional potency (EC50) near 194 nM. At the delta-opioid receptor it is a much weaker agonist, with a Ki above 10 micromolar. That roughly 200-fold preference for mu over delta in human tissue is the reason receptor studies read tianeptine as a mu-opioid tool first.

The Concentrations Receptor And Cell Studies Actually Use

In-vitro studies work in the nanomolar to micromolar range, tracking the functional numbers above rather than any milligram figure. A cell assay measuring mu-opioid activation sits near the 194 nM human EC50; one probing the delta receptor has to climb into the tens of micromolar to see an effect. That spread, three orders of magnitude between the two receptors, is a property of the molecule, not a difference in method.

Species shifts the same measurement, and this is the first hard wall for cross-study comparison.

The mouse mu-opioid receptor needed roughly three times the concentration of the human receptor to reach the same activation in Gassaway's data. Read two in-vitro studies that used different species at the same nanomolar concentration and you are not looking at the same treatment level, even though the numbers on the page match.

How Much Do Animal Studies Administer, And By What Route?

Animal studies commonly work between 0.25 and 10 mg per kilogram, given by injection. A 2010 review in the journal Pharmaceuticals summarizes rat work that administered tianeptine intraperitoneally at five treatment levels, 0.25, 0.50, 1, 5, and 10 mg/kg, as a single injection before a memory task, with the 1, 5, and 10 mg/kg levels producing a measurable effect at 24 hours.

Route is the variable most often glossed over. Intraperitoneal injection is standard in the rodent behavioral literature because it is fast and repeatable, but oral and subcutaneous routes appear too, and each delivers a different fraction of the material to circulation on a different time course. A published rat pharmacokinetic study compared routes directly for exactly this reason. Tianeptine also clears quickly, with a short elimination half-life reported in the pharmacokinetic literature, which is why chronic-exposure studies administer the material daily rather than weekly: it does not linger, so holding an exposure level steady means giving it again.

Salt Form Changes The Amount On The Label

Here is the claim most tianeptine writing gets wrong: 10 mg is not 10 mg. Because the salt forms carry different counterions, an equal mass of each holds a different molar amount of the active tianeptine cation, and the receptor responds to moles, not milligrams.

Run the table numbers. Ten milligrams of the free acid is about 22.9 micromoles of tianeptine. The same 10 mg of the sodium salt is about 21.8 micromoles, roughly 5% less. Ten milligrams of a 1:1 sulfate salt is about 18.7 micromoles, roughly 18% less than the free acid. A study that reports "10 mg/kg" without naming the salt has left out the information needed to reproduce it. This is not a rounding problem; an 18% gap in delivered material is larger than the difference between several of the animal treatment levels above. When a client stocks both the sodium and the sulfate salt, the label difference is the researcher's problem to solve, and the certificate of analysis is where the exact salt is named.

Species And Route Change What A Number Means

Species and route are the two variables that survive even after you fix the salt-form math. The mu-opioid potency gap between human and mouse tissue is real and measured, and the route decides how much of an administered amount ever reaches the receptor.

Take two rodent studies that both report 5 mg/kg. If one injected intraperitoneally and the other dosed orally, the circulating exposure levels differ, because first-pass handling and absorption differ by route. Add a species change, rat versus mouse, and the receptor sensitivity differs on top of that. Neither study is wrong. They are simply not measuring the same thing, and stacking their conclusions as if "5 mg/kg" were a fixed quantity produces a false agreement or a false conflict.

How Do You Compare Amounts Across Tianeptine Research Studies?

Normalize before you compare. The method has four steps, and it turns a pile of incompatible numbers into a single scale.

First, identify the salt form from the paper or the certificate of analysis, and convert every stated mass to moles of the tianeptine cation using the correct molecular weight (436.95 for the free acid, 458.9 for the sodium salt, and the supplier-confirmed figure for the sulfate). Second, record the route, because an intraperitoneal amount and an oral amount are not interchangeable. Third, record the species, since the human and mouse receptors answer differently to the same concentration. Fourth, confirm the material's identity and purity, because the whole calculation rests on the stated mass being real. Do those four things and tianeptine research studies line up on a common axis; skip any one and the comparison quietly breaks.

Why Verified Identity And Purity Decide Whether A Number Is Real

Every number above assumes the material is what the label says. An unverified identity or an unstated purity makes the milligram meaningless, because you are converting a mass you cannot trust. Identity and purity are the floor under the entire comparison, not a footnote to it.

This is where supplier documentation stops being paperwork and becomes data. Nordic Chems guarantees 99% purity across every batch, verified by HPLC, mass spectrometry, and LC-MS through BioRegen Labs in Houston and Janoshik Analytical in Prague, with the operation running under ISO 9001:2015 (certificate C2024-01140). A batch below the 99% threshold is not used; another batch is tested and run in its place. The certificate of analysis carries a batch or lot number and a test date, and a buyer can match it to the exact lot received by emailing the order number. That traceability is the difference between a reproducible protocol and a hopeful one.

The track record behind those controls is part of why researchers choose a documented supplier: 10,600 orders shipped, 20 batches tested with more in progress, a 25% all-time repeat-customer rate, and a 4.8-star Google rating, over a year in operation.

Is Tianeptine Legal For Research In 2026?

Its legal position is changing right now, and any research plan has to account for it. On July 8, 2026, the DEA published a proposed rule (docket DEA1596) to place tianeptine in Schedule I, in the opioids category at 21 CFR 1308.11(b). The public comment and hearing period closed on August 7, 2026. The rule is not final as of this writing, but HHS recommended Schedule I placement in July 2025, so the direction is set.

Read the proposal's own language on who it touches. It states that any person who manufactures, distributes, imports, exports, engages in research with, or possesses tianeptine "would need to be registered with DEA" if the rule finalizes, with a 90-day window for already-registered Schedule I researchers to file modified applications. In plain terms, a final rule would move tianeptine out of the open research-material market and into the controlled-substance system.

The DEA grounded the proposal on three findings: tianeptine is pharmacologically similar to mu-opioid agonists including morphine and fentanyl, it has no currently accepted US medical use, and it lacks accepted safety for use under medical supervision. The supporting record cites poison center calls rising from 11 across 2000 to 2013 to 207 across 2014 to 2017 (81 in 2017 alone), exposures up roughly 1,400% from 2015 to 2023, at least four fatal cases involving tianeptine, and 268 forensic encounters logged between March 2017 and February 2026. Fifteen states already control it: Alabama, Arkansas, Florida, Georgia, Indiana, Kentucky, Louisiana, Maryland, Michigan, Minnesota, Mississippi, Ohio, Oklahoma, Tennessee, and Virginia.

For a research buyer, the compliance step is not optional. Confirm your own jurisdiction before you order, and track the federal rule to its outcome, because possession terms may change under you. Nordic Chems ships within the USA and Canada only, vets every order before it ships against shipping profiles that block restricted states, and requires buyers to declare they are trained professionals handling the material properly. Lawful possession sits with the buyer, not the vendor. Tianeptine is sold for laboratory research and educational use only, not for human consumption.

Conclusion

The number printed in a tianeptine paper is rarely the number you can compare. A study that injects 10 mg per kilogram of the sodium salt into a rat is not describing the same molar exposure as one that uses the free acid or the sulfate, and a nanomolar concentration in a cell assay lives in a different world again. Line the studies up by converting every stated mass to moles of the tianeptine cation, then match route and species before you draw a single conclusion. Confirm the material is what the label claims, because an unverified identity turns every calculation into a guess. And read tianeptine research studies against the 2026 record: the DEA has proposed Schedule I placement, and the compliance question now travels with the science. Treat the amount, the identity, and the legal status as one problem, and the comparison finally holds.

Research use only. Tianeptine is sold and described here strictly for in-vitro laboratory research and educational purposes. It is not for human or animal consumption, is not a food or a supplement, and is not for any therapeutic use. Nothing here is medical, legal, or professional advice, and nothing here describes or recommends human use. As of August 2026 the DEA has proposed placing tianeptine in Schedule I; the rule is not final, and legal status can change. Always read the safety data sheet for your specific batch, confirm your jurisdiction's current rules, and comply with all local, state, and federal regulations for handling, storage, transport, and disposal.

Frequently Asked Questions

What do tianeptine research studies mean by "amount administered"? 

It is the quantity of material given to a research model, stated as a concentration for cell studies (nanomolar to micromolar) or as mass per body weight for animal studies (commonly 0.25 to 10 mg/kg). Across tianeptine research studies the figure is only comparable once you know the salt form, route, and species behind it. Tianeptine is for laboratory research and educational use only, not for human consumption.

Why do reported tianeptine amounts differ across studies? 

Three variables move the number: salt form, route of administration, and species. The salt form changes the molar amount in a given mass, the route changes how much reaches the target, and the species changes how the receptor responds. In tianeptine research studies, a stated milligram figure without those three details cannot be reproduced.

How do you convert between tianeptine salt forms? 

Convert the stated mass to moles using the correct molecular weight: 436.95 g/mol for the free acid and 458.9 g/mol for the sodium salt. Ten milligrams of the free acid is about 22.9 micromoles of tianeptine; the same mass of the sodium salt is about 21.8 micromoles, roughly 5% less. Confirm the sulfate figure against the certificate of analysis, since salt stoichiometry varies.

What receptor does tianeptine act on in research? 

Tianeptine is a full agonist at the mu-opioid receptor, shown by Gassaway and colleagues in 2014, with a human functional potency (EC50) near 194 nM and no appreciable activity at monoamine transporters or glutamate receptors. It is a much weaker delta-opioid agonist and inactive at the kappa receptor.

Is tianeptine legal to buy for research in the United States in 2026? 

As of this writing, tianeptine is not yet federally scheduled, but on July 8, 2026, the DEA proposed placing it in Schedule I, and fifteen states already control it. A final federal rule would require anyone handling tianeptine, including researchers, to register with the DEA. Confirm your jurisdiction before ordering, since lawful possession is the buyer's responsibility.

How do you verify tianeptine identity and purity before research? 

Match the batch or lot number on the label to the certificate of analysis, then check the purity figure and the method behind it. Nordic Chems guarantees 99% purity verified by HPLC, mass spectrometry, and LC-MS, and rejects any batch below that threshold. You can match your COA to your order by email.

What amounts do animal studies administer? 

Rodent behavioral studies commonly work between 0.25 and 10 mg/kg by injection. One rat memory study administered five treatment levels intraperitoneally (0.25, 0.50, 1, 5, and 10 mg/kg), with the 1, 5, and 10 mg/kg levels producing an effect at 24 hours. The route and salt form have to be recorded for the figure to be reproducible.

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