What Is Tesofensine? Dosage, Half-Life & How to Track It

What tesofensine is and how it works

Tesofensine (development code NS2330) was created by the Danish biotech NeuroSearch as a candidate for Parkinson’s disease and Alzheimer’s, working through triple monoamine reuptake inhibition — blocking the reabsorption of norepinephrine, dopamine, and serotonin, which increases their availability in the brain. This is a fundamentally different mechanism from GLP-1 drugs like semaglutide, which act on a gut-hormone receptor; tesofensine works centrally, more like a stimulant/antidepressant hybrid than a metabolic hormone.

The weight-loss signal turned up as a side finding in the neurological trials, prompting a dedicated Phase 2 obesity trial (TIPO-1, published in *The Lancet*, 2008) that showed dose-dependent weight loss substantially larger than most obesity drugs of that era. But the same trial surfaced the problem that stalled further development: measurable increases in resting heart rate and blood pressure at the doses that worked best, a cardiovascular signal serious enough that NeuroSearch did not advance tesofensine to Phase 3 for obesity on its own.

The idea didn’t die — Saniona, which later acquired the compound, has studied a combination called Tesomet (tesofensine paired with the beta-blocker metoprolol, specifically to offset the heart-rate increase) in trials for rare conditions like hypothalamic obesity and Prader-Willi syndrome. Standalone tesofensine, however, has no FDA approval for any use, and where it circulates today is mainly through compounding pharmacies and research-chemical sourcing — a materially different regulatory and quality-control situation than an approved drug.

Typical dosing

Because tesofensine isn’t an approved drug, there is no official prescribing label — the numbers below reflect the original Phase 2 trial design, not a validated commercial protocol. It is taken orally, with no reconstitution step.

• Doses studied in the pivotal trial: 0.25 mg, 0.5 mg, and 1.0 mg once daily
• 0.5 mg is generally cited as the point of best balance between effect size and tolerability in that trial
• Compounded/community protocols commonly start at the lowest studied dose given the cardiovascular signal at higher doses

Half-life & what it means for frequency

Tesofensine’s half-life is unusually long for an oral small molecule — reported in the range of 8–10 days, driven by extensive distribution into body tissue rather than the albumin-binding trick semaglutide uses. That supports once-daily dosing, but it also means the drug builds up slowly over several weeks before reaching a steady level, so week six on a dose looks different from week one.

The same long half-life cuts the other way if something goes wrong: unlike a short-acting oral drug you can stop and clear within a day, tesofensine’s effects — including the cardiovascular ones — take weeks to fully wash out after stopping. That is a genuinely important safety distinction from most other oral compounds in this library.

What to track & side effects

The two effects worth taking most seriously are the ones that stalled its original development: increased resting heart rate and blood pressure, dose-dependent and present even at the doses that produced the best weight-loss results. Beyond that, commonly reported effects include dry mouth, insomnia, and constipation — a side-effect pattern more typical of a CNS stimulant than a gut-hormone drug, which tracks with its actual mechanism.

Given the cardiovascular signal, the most useful things to log are the ones a doctor would actually want to see: resting heart rate and blood pressure alongside each dose, not just weight. Because of the slow multi-week build-up, weight trend needs to be read over a longer window than a shorter-half-life compound — a single week is not a fair test.

Frequently asked questions