Reviewed & approved by Dr. Nova Reyes · Last checked 2026-10-25. ← Back to Evidence Library
Tesofensine: what the evidence says
At a glance
Oral non-peptide small molecule: tesofensine is a pill, not a peptide, but research-peptide vendors sell it, so we include it alongside the peptides people compare it with. Reports of approval in Mexico: UNVERIFIED, not checked against COFEPRIS. A 2026 anti-doping paper describes it as "still under regulatory review" and sold online as a supplement. R5
What it is: a "triple reuptake inhibitor" that raises brain levels of noradrenaline, dopamine and serotonin, reducing appetite. R1
What the evidence says: one phase 2 trial (203 people) found much more weight loss than placebo, but The Lancet later issued an expression of concern about that paper. One small trial in hypothalamic obesity (combined with metoprolol) also found weight loss. Phase 3 results: not found in PubMed. R1, R2, R4
Biggest risks: raised heart rate, dry mouth, insomnia, and mood/anxiety effects. R1, R4
Rating
| Human Human (weight) | Limited: one phase 2 RCT under a journal expression of concern, plus one 21-person RCT of a combination product R1, R2, R4 |
| Animal Animal evidence | Not rated here |
| Regulatory | Not FDA-approved (no Drugs@FDA record) · Mexico: reported approved for obesity [UNVERIFIED: not confirmed on COFEPRIS primary registry] · WADA 2026: prohibited in-competition (S6.b specified stimulant, named) R6 |
| Established human dose | None. No approved label. Trial arms are in Study details |
Evidence verdict: Human (weight): Limited Card verdict: Limited (weight loss, phase 2 trial under expression of concern)
This page reports what studies used. It is not dosing advice.
Legend: HUMAN data · ANIMAL / LAB data · UNKNOWN · UNVERIFIED: not yet confirmed against a primary source
What is it?
Tesofensine (NS-2330) was first developed for Parkinson's and Alzheimer's disease, then for obesity. R1 It blocks the recycling of three brain messengers, which suppresses appetite.
Does it work?
- Human Obesity (phase 2, Denmark): after about six months on a calorie-restricted diet, people lost 4.5% to 10.6% of body weight on tesofensine vs 2.0% on placebo. R1 The Lancet published an expression of concern about this paper in 2013. R2
- Human Hypothalamic obesity: in 21 adults, a tesofensine + metoprolol combination (Tesomet) gave 6.3% more weight loss than placebo. Sponsored by Saniona. R4
- Unknown Phase 3 trials: reported by the developer, but we did not find peer-reviewed results.
Is it safe?
- Caution Heart rate: rose by 7.4 beats per minute in the middle phase 2 arm vs placebo. R1
- Caution Common side effects: dry mouth, nausea, constipation, diarrhoea and insomnia. R1
- Caution Mood: one person on Tesomet had worsened anxiety leading to stopping. R4
- Human Abuse potential: in 52 recreational stimulant users, it did not feel like amphetamine. R3
Gray-market "research use only" Tesofensine: extra risks
Unknown contents. Products sold online as "research use only" or "not for human use" are not made under drug-quality rules, so identity, strength and sterility are unknown. This is a general caution; we have not found testing data for this product specifically. Unknown
Sold as a "supplement". Anti-doping researchers bought tesofensine marketed online as a dietary supplement. R5
What we don't know
- Unknown Long-term heart and blood-pressure safety
- Unknown Peer-reviewed phase 3 results
- Unknown Mexican regulatory status (not checked)
Is it legal?
Not FDA-approved in the US (no Drugs@FDA record, openFDA query Oct 24, 2026). Mexico: UNVERIFIED, not checked against COFEPRIS. EU, UK, Japan, China: UNVERIFIED not checked against EMA, MHRA, PMDA or NMPA. WADA: named under S6.b (specified stimulants), prohibited in-competition R6.
Study details
These are doses researchers used, not recommendations.
R1 Human Human: Phase 2 obesity RCT (Astrup 2008, expression of concern 2013)
NCT00394667. 203 adults, BMI 30–40, energy-restricted diet.
| Study | People / model | Route | Dose used | Follow-up | Reported | Side effects / dropouts | Citation |
|---|---|---|---|---|---|---|---|
| Astrup 2008 | 52 | Oral | Placebo once daily | 24 wk | −2.0% | 79% completed overall | PMID 18950853 |
| Astrup 2008 | 52 | Oral | Tesofensine 0.25 mg once daily | 24 wk | −4.5% | Dry mouth, nausea, constipation, diarrhoea, insomnia | PMID 18950853 |
| Astrup 2008 | 50 | Oral | Tesofensine 0.5 mg once daily | 24 wk | −9.2% | Heart rate +7.4 bpm vs placebo | PMID 18950853 |
| Astrup 2008 | 49 | Oral | Tesofensine 1.0 mg once daily | 24 wk | −10.6% | As above | PMID 18950853 |
R2: Lancet expression of concern, 2013. PMID 23561987
R3 Human Human abuse-potential study (Schoedel 2010)
52 recreational stimulant users, single-amount crossover; amounts not in abstract. PMID 20520602
R4 Human Human: Tesomet in hypothalamic obesity (Huynh 2022)
| Study | People / model | Route | Dose used | Follow-up | Reported | Side effects / dropouts | Citation |
|---|---|---|---|---|---|---|---|
| Huynh 2022 | 21 randomized (18 completed) | Oral | Tesofensine 0.5 mg + metoprolol 50 mg | 24 wk | −6.3% vs placebo | Sleep problems 50% vs 13%; dry mouth 43% vs 0%; 1 anxiety SAE | PMID 35294397 |
R5 Human Human: Urine metabolism / anti-doping (Krug 2026)
6 volunteers took a supplement containing 483 µg tesofensine; detection up to 500 h. PMID 42320973
Full reference list (PubMed entries verified Oct 24, 2026)
- R1 Astrup A, et al. Lancet. 2008;372(9653):1906-13. PMID 18950853
- R2 Expression of concern. Lancet. 2013;381(9873):1167. PMID 23561987
- R3 Schoedel KA, et al. Clin Pharmacol Ther. 2010;88(1):69-78. PMID 20520602
- R4 Huynh K, et al. Eur J Endocrinol. 2022;186(6):687-700. PMID 35294397
- R5 Krug O, et al. Drug Test Anal. 2026;18(9):1163-73. PMID 42320973
- R6 WADA. World Anti-Doping Code International Standard: Prohibited List 2026 (in force Jan 1, 2026). https://www.wada-ama.org/sites/default/files/2025-09/2026list_en_final_clean_september_2025.pdf (text read Oct 24, 2026)
Disclaimer
This page summarizes published research for education and harm reduction; it is not medical advice or a recommendation to use Tesofensine. Talk to a clinician you trust before using any drug, and report side effects to FDA MedWatch.
Approved for Adam Greene by Dr. Nova Reyes, 2026-10-25.