A reference work, not a recommendation to use: this profile describes mechanism and evidence and does not replace medical advice. The claims come from marketing and forums and are tested here, not endorsed.

Claims checked

  • Works like Ozempic: marked weight loss

    Small benefit

    Energy & metabolism · mixed: adults in RCTs (composition not examined in detail) · Human, randomised

    Meta-analysis of 23 papers: −0.88 kg body weight, −0.48 kg/m² BMI, with deficiencies in blinding and product information [12]. In STEP 1, semaglutide lowered weight by 12.7 kg more than placebo [13]; the GLP-1 effect of berberine has been shown only in rats and in cells [4].

  • Lowers blood sugar and HbA1c

    Only proven in patients

    Energy & metabolism · healthy · Human, randomised

    In type 2 diabetes, HbA1c fell by 0.99 versus 0.59 percentage points in a large placebo-controlled study [8], and by 0.73 percentage points in a meta-analysis [10]. Studies in healthy people with normal metabolism were not found.

  • Lowers cholesterol and triglycerides

    Only proven in patients

    Heart & blood vessels · healthy · Human, randomised

    In dyslipidemia, small reduction in LDL cholesterol (−0.46 mmol/l) and triglycerides (−0.34 mmol/l) in 18 placebo-controlled studies [11]; clinical endpoints are lacking, data in healthy people not found.

  • Activates AMPK and works like metformin against aging

    Not studied

    Longevity · healthy · Animal study

    AMPK activation via inhibition of the respiratory chain has been shown only in cells and rodents [1][2]; studies on aging or lifespan in humans were not found.[1][2]

Mechanism of action

Evidence map: Berberine

Each line stands for a published finding; line style and color show where it comes from. The filter hides weaker evidence levels. Sources: see references.

In fat cells and muscle cells, berberine activated AMP-activated protein kinase (AMPK) and promoted translocation of the glucose transporter GLUT4; in diabetic db/db mice and rats fed a high-fat diet, body weight and triglycerides fell and glucose tolerance improved [1]. The reason is probably an energy deficit in the cell: like metformin, berberine inhibits complex I of the respiratory chain, and AMPK activation depended on neither LKB1 nor CaMKKβ [2]. Independently of this, berberine stabilizes the mRNA of the LDL receptor in liver cells; in hamsters, its mRNA rose 3.5-fold and the protein 2.6-fold [3]. In rats, berberine enhanced the glucose-induced release of the gut hormone GLP-1 over five weeks, and in a human L-cell line, GLP-1 release rose in a concentration-dependent manner [4]. These animal and cell data are the only basis for the comparison with semaglutide, which itself activates the GLP-1 receptor.

Orally, berberine barely reaches the circulation. In rats, absolute bioavailability was 0.36%; about half passed through the intestine unchanged, the other half was broken down in the intestinal wall, and in the liver the area under the curve was 70-fold higher than in plasma [5]. In humans, berberrubine is the most important metabolite in plasma [6]. In a pilot study with five young men, plasma berberine reached on average only 0.4 ng/ml after berberine administration; the derivative dihydroberberine led to higher berberine levels, and the study leader consults for a manufacturer [7]. The low systemic availability supports the hypothesis that berberine acts via the gut: in a placebo-controlled study with 409 people with newly diagnosed type 2 diabetes, HbA1c fell by 0.99 percentage points under berberine versus 0.59 under placebo; metagenome analyses linked the effect to an inhibited conversion of deoxycholic acid by Ruminococcus bromii [8]. This is an association within the study, not proof of causality.

Clinically, there are many studies, predominantly Chinese. In a small randomized pilot study with 36 people with newly diagnosed type 2 diabetes, berberine lowered blood glucose similarly to metformin, with HbA1c falling from 9.5% to 7.5%; overall, 20 participants (34.5%) had transient gastrointestinal complaints [9]. A meta-analysis of 46 studies found an HbA1c reduction of 0.73 percentage points, often as an add-on to standard therapy [10]. A meta-analysis of 18 placebo-controlled studies with 1788 people with dyslipidemia gave LDL cholesterol −0.46 mmol/l and triglycerides −0.34 mmol/l; 83% of the studies came from China and Hong Kong [11]. For body weight, the pooled difference was −0.88 kg (23 papers); the authors criticize missing blinding and inadequate information on the products [12]. For comparison: in the pivotal trial STEP 1, semaglutide lowered weight over 68 weeks by 14.9% versus 2.4% under placebo, that is, 12.7 kg more [13]. A direct comparison of the two substances was not found.

Berberine is not pharmacologically harmless. In 18 healthy men, it inhibited CYP2D6 after two weeks (dextromethorphan to dextrorphan ratio increased 9-fold), CYP2C9 (losartan to E-3174 ratio doubled), and CYP3A4 (midazolam area under the curve increased by 40%) [14]. In the laboratory, berberine displaces bilirubin from albumin about ten times more strongly than phenylbutazone, and in rats free bilirubin rose; the author advises against berberine-rich products in newborns with jaundice and in pregnancy [15].

Synaptik serves solely to explain biochemistry and pharmacology and is not medical advice or a recommendation to take anything.

Mechanism of action only. Schematic cutaway, not to scale: on the left a body cell with the nutrient switches AMPK and mTORC1, on the right two senescent cells. Particles, speeds and switch positions are illustrative and only show the direction of a finding; the switch bar says where it comes from (cell culture, animal or human). Lifespan findings come from worms and mice; human lifespan has not been studied with any of these drugs.

Complex I damped · AMPK on (cell culture) · rise in AMP not shown

AMPK
oncell culture
mTORC1
not measured
Autophagy
not measured
Senescent cells
not measured
Drug
View

ATP  AMP  amino acids  SASP  mTORC1 inhibitors  AMPK activators  Autophagy  Senolytics  particles illustrative

Berberine activated AMPK in fat and muscle cells and promoted GLUT4 translocation [20]. The respiratory chain is thought to be the cause: berberine inhibited complex I in muscle cells and isolated muscle mitochondria, and AMPK activation depended on neither LKB1 nor CaMKKβ (cell culture) [21]. The profile's sources do not report a rise in AMP, so the figure does not show one. Whether enough berberine reaches the cells is questionable: in rats, absolute oral bioavailability was 0.36%, and the area under the curve was 70 times higher in the liver than in plasma [22]. There are no lifespan data.

Tap or focus a labelled part for a one-line explanation.

Also acting here, not drawn

What the figure shows, and how sure we are

Mechanism-of-action explainer only. Not medical advice, and no statement about benefit, risk, amount or use. Sirolimus, everolimus, metformin, canagliflozin and dasatinib are prescription medicines; none of them is approved for use against ageing.

What was simplified. One cell stands for many cell types; the findings come from liver, muscle, fat and heart cells of different species, and the figure only shows where each drug acts. Sizes, numbers of organelles, particles and speeds are illustrative; glucose output applies to liver cells only. The signal lines stand for several intermediate steps (for example AMPK via TSC2 and Raptor). Switches marked “not measured” do not follow the textbook pathway: whether metformin, for instance, increases autophagy in these cells is not stated in the profile's sources. Drugs are drawn as markers, not as skeletal formulas. Calcium alpha-ketoglutarate, pentadecanoic acid, sulforaphane, TUDCA and further substances are listed at this site in the figure catalogue but are not drawn; the reasons are given in the list below the figure. The γ subunit is drawn with four CBS domains, with nucleotides only at the three binding sites from [3]. The numbers in [5], [6], [8] to [15] and [17] to [35] come from the Synaptik profiles of the drugs, where they were checked against the sources. [1] and [2] were checked against the full text, [3], [4], [7] and [16] against the PubMed abstract (25 Oct 2026).

Targets

TargetTypeActionKey dataEvidence
AMP-activated protein kinase (AMPK)Signaling pathwayActivatorindirect, independent of LKB1 and CaMKKβ (cell culture) Laboratory[1][2]
Respiratory chain complex IEnzymeInhibitordose-dependent (L6 myotubes, muscle mitochondria) Laboratory[2]
LDL receptor (mRNA stabilization)ReceptorExpression ↑liver mRNA 3.5-fold, protein 2.6-fold (hamster) Animal study[3]
GLP-1 release from L cellsHormone axisRelease Animal study[4]
CYP2D6EnzymeInhibitorDextromethorphan/dextrorphan in urine 9-fold (human) Human, randomised[14]
CYP2C9EnzymeInhibitorLosartan/E-3174 doubled (human) Human, randomised[14]
CYP3A4EnzymeInhibitorMidazolam AUC +40%, clearance −27% (human) Human, randomised[14]
Bilirubin binding site of albuminOtherBindingDisplacement about 10-fold stronger than phenylbutazone (in vitro) Animal study[15]

Effect profile

Which signaling systems the compound affects according to current data. ↑ enhanced, ↓ dampened, ≈ modulated, ○ no effect; dots = evidence level.

  • Dopamineno data
  • Noradrenalineno data
  • Serotoninno data
  • Acetylcholineno data
  • Glutamate · AMPAno data
  • Glutamate · NMDAno data
  • GABAno data
  • Histamineno data
  • Orexinno data
  • Adenosineno data
  • Opioidsno data
  • Melatoninno data
  • Neurotrophinsno data
  • Blood flowno data
  • Nitric oxideno data
  • Energy metabolismmodulated · inhibits complex I of the respiratory chain and thereby activates AMPK (cell culture)[1][2]
  • Insulin · glucose↓ · HbA1c and fasting glucose lowered in type 2 diabetes (RCTs, meta-analysis); not shown in healthy people[8][9][10]
  • Inflammation · oxidativeno data
  • Stress axisno data
  • Testosterone axisno data
  • Endocannabinoidsno data
  • Autophagy · senescenceno data
  • Immune systemno data
  • Lipid metabolismno data
  • Coagulation · fibrinolysisno data
  • Methylationno data

Routes of administration and bioavailability

How much of a compound reaches the blood or target tissue depends on the route into the body and on the dosage form. All routes of administration explained

  • Oral (swallowed) · Berberine (chloride or hydrochloride)

    ≈ 0.36% absolute (rat)

    Extensive breakdown already in the intestinal wall, accumulation in the liver [5]. Very low plasma levels in humans (on average 0.4 ng/ml in five men) [7]; main metabolite in plasma is berberrubine [6].

    Human, non-randomised

  • Oral (swallowed) · Dihydroberberine

    higher berberine levels than after berberine (pilot study, 5 people)

    Randomized crossover pilot study without an effect on glucose or insulin; the study leader is a paid consultant of a manufacturer [7]. Better efficacy in rodents, presumably through higher bioavailability [2].

    Human, randomised

Human studies

  • PREMOTE: berberine and probiotics in type 2 diabetes

    RCT, double-blind, placebo-controlled, 4 arms, 20 centers · Patients: newly diagnosed type 2 diabetes · n = 409 · 12 weeks

    Measured: HbA1c

    Result: Berberine alone −0.99 percentage points, placebo −0.59; more gastrointestinal adverse effects.[8]

    Human, randomised

  • Meta-analysis, type 2 diabetes

    systematic review and meta-analysis of RCTs · Patients: type 2 diabetes

    Measured: HbA1c, fasting glucose, blood lipids

    Result: 46 studies; HbA1c −0.73 percentage points (95% CI −0.97 to −0.51), often as add-on therapy.[10]

    Human, randomised

  • Meta-analysis, dyslipidemia

    systematic review and meta-analysis of placebo-controlled RCTs · Patients: dyslipidemia · n = 1788 · 4–24 weeks

    Measured: LDL-C, Triglyceride, HDL-C, ApoB

    Result: LDL-C −0.46 mmol/l, triglycerides −0.34 mmol/l; gastrointestinal complaints tended to be more frequent.[11]

    Human, randomised

  • Meta-analysis, body weight

    systematic review and meta-analysis of RCTs · Adults (mixed)

    Measured: Weight, BMI, waist circumference

    Result: 23 papers; weight −0.88 kg (95% CI −1.36 to −0.39), BMI −0.48 kg/m².[12]

    Human, randomised

  • Pilot study against metformin

    randomized, comparison with metformin (substudy A); open-label add-on treatment (substudy B) · Patients: type 2 diabetes · n = 84 · 3 months

    Measured: HbA1c, fasting and postprandial glucose

    Result: Substudy A (36): similar to metformin, HbA1c 9.5% to 7.5%; 34.5% transient gastrointestinal complaints.[9]

    Human, randomised

  • CYP inhibition in healthy people

    randomized, crossover, placebo phase · healthy (men) · n = 18 · 2 weeks

    Measured: Activity of CYP3A4, 2C19, 2D6, 2C9, 1A2 (probe substances)

    Result: CYP2D6, 2C9, and 3A4 inhibited; 17 people completed the study.[14]

    Human, randomised

  • Plasma levels of berberine vs. dihydroberberine

    randomized, double-blind, crossover, pilot study · healthy (men) · n = 5 · 4 administrations per condition

    Measured: Berberine in plasma, glucose, insulin

    Result: Berberine Cmax after berberine 0.4 ng/ml, higher after dihydroberberine; glucose and insulin unchanged.[7]

    Human, randomised

Risks and warnings

  • Gastrointestinal complaints

    Transient complaints in 34.5% in a pilot study [9], more frequent than with placebo in a large RCT [8] and tendentially so in a meta-analysis (2–23% versus 2–15%) [11].

    Human, randomised

  • Inhibition of CYP enzymes

    Inhibited activity of CYP2D6, CYP2C9, and CYP3A4 in healthy people after two weeks; levels of drugs broken down via these enzymes may rise [14].

    Human, randomised

  • Newborns and pregnancy

    Displaces bilirubin from albumin (in vitro) and raised free bilirubin in rats; berberine-containing medicinal plants have been linked to kernicterus in newborns [15].

    Animal study

Interactions

  • Substrates of CYP2D6, CYP2C9, and CYP3A4 (e.g., dextromethorphan, losartan, midazolam): Increased levels or reduced breakdown of the probe substances after two weeks of berberine [14].
  • Metformin and other blood sugar–lowering drugs: Similar glucose lowering to metformin in a pilot study [9] and action at the same target (complex I) in cells [2]; studies on the combination and on the risk of hypoglycemia were not examined.

Fact check: common claims

  • refuted

    “Berberine is “nature’s Ozempic.””

    Pooled weight loss −0.88 kg [12] versus 12.7 kg additional loss under semaglutide in STEP 1 [13]; a GLP-1 effect has been shown only in rats and in cells [4]. No direct comparison, but the magnitudes are more than tenfold apart.

  • partly supported

    “Berberine lowers blood sugar as strongly as metformin”

    Similarly effective in one small randomized pilot study with 36 people [9]; HbA1c reduction confirmed in a meta-analysis and a large RCT [8][10], but only in type 2 diabetes and without large comparison studies.

  • partly supported

    “Berberine activates AMPK”

    Shown in cells and rodents, probably indirectly via inhibition of the respiratory chain [1][2]; not demonstrated in human tissue.

  • partly supported

    “Berberine acts mainly via the gut flora”

    Low bioavailability [5] and metagenome findings in a large RCT [8] support the hypothesis; proof of causality in humans is lacking.

  • refuted

    “Being a natural compound, berberine has no interactions”

    Inhibits CYP2D6, CYP2C9, and CYP3A4 in humans [14] and displaces bilirubin from albumin [15].

Pharmacokinetics

Absorption
Very low; absolute bioavailability 0.36% in rats, plasma levels in humans in the range of a few ng/ml or below [5][7].
Half-life
Not verified.
Metabolism
Extensive breakdown in the intestinal wall (rat) [5]; in humans, berberrubine is the most important plasma metabolite [6].
Entry into the brain
Not verified.

Legal status

Germany
Not verified.
EU
Not verified.
USA
Not verified.
Other countries
According to a meta-analysis, readily available as a food supplement or over-the-counter medicine [11]; approval status not checked.

Related compounds

Curcuminsame classMetforminsame class

Open questions

  • What effects does berberine have in people without a metabolic disease?
  • How robust are the results when only blinded, preregistered studies from outside China are considered?
  • Is the gut (microbiome, bile acids) really the main site of action?
  • Does berberine lower clinical endpoints such as myocardial infarction or diabetic complications?

References

  1. Lee YS, Kim WS, Kim KH, Yoon MJ, Cho HJ, Shen Y, et al. Berberine, a natural plant product, activates AMP-activated protein kinase with beneficial metabolic effects in diabetic and insulin-resistant states. Diabetes. 2006;55(8):2256–64. doi:10.2337/db06-0006 · PubMed
  2. Turner N, Li JY, Gosby A, To SW, Cheng Z, Miyoshi H, et al. Berberine and its more biologically available derivative, dihydroberberine, inhibit mitochondrial respiratory complex I: a mechanism for the action of berberine to activate AMP-activated protein kinase and improve insulin action. Diabetes. 2008;57(5):1414–8. doi:10.2337/db07-1552 · PubMed
  3. Kong W, Wei J, Abidi P, Lin M, Inaba S, Li C, et al. Berberine is a novel cholesterol-lowering drug working through a unique mechanism distinct from statins. Nat Med. 2004;10(12):1344–51. doi:10.1038/nm1135 · PubMed
  4. Yu Y, Liu L, Wang X, Liu X, Liu X, Xie L, et al. Modulation of glucagon-like peptide-1 release by berberine: in vivo and in vitro studies. Biochem Pharmacol. 2010;79(7):1000–6. doi:10.1016/j.bcp.2009.11.017 · PubMed
  5. Liu YT, Hao HP, Xie HG, Lai L, Wang Q, Liu CX, et al. Extensive intestinal first-pass elimination and predominant hepatic distribution of berberine explain its low plasma levels in rats. Drug Metab Dispos. 2010;38(10):1779–84. doi:10.1124/dmd.110.033936 · PubMed
  6. Spinozzi S, Colliva C, Camborata C, Roberti M, Ianni C, Neri F, et al. Berberine and its metabolites: relationship between physicochemical properties and plasma levels after administration to human subjects. J Nat Prod. 2014;77(4):766–72. doi:10.1021/np400607k · PubMed
  7. Moon JM, Ratliff KM, Hagele AM, Stecker RA, Mumford PW, Kerksick CM. Absorption kinetics of berberine and dihydroberberine and their impact on glycemia: a randomized, controlled, crossover pilot trial. Nutrients. 2021;14(1):124. doi:10.3390/nu14010124 · PubMed
  8. Zhang Y, Gu Y, Ren H, Wang S, Zhong H, Zhao X, et al. Gut microbiome-related effects of berberine and probiotics on type 2 diabetes (the PREMOTE study). Nat Commun. 2020;11(1):5015. doi:10.1038/s41467-020-18414-8 · PubMed
  9. Yin J, Xing H, Ye J. Efficacy of berberine in patients with type 2 diabetes mellitus. Metabolism. 2008;57(5):712–7. doi:10.1016/j.metabol.2008.01.013 · PubMed
  10. Guo J, Chen H, Zhang X, Lou W, Zhang P, Qiu Y, et al. The effect of berberine on metabolic profiles in type 2 diabetic patients: a systematic review and meta-analysis of randomized controlled trials. Oxid Med Cell Longev. 2021;2021:2074610. doi:10.1155/2021/2074610 · PubMed
  11. Blais JE, Huang X, Zhao JV. Overall and sex-specific effect of berberine for the treatment of dyslipidemia in adults: a systematic review and meta-analysis of randomized placebo-controlled trials. Drugs. 2023;83(5):403–27. doi:10.1007/s40265-023-01841-4 · PubMed
  12. Elahi Vahed I, Shahir-Roudi E, Nojumi S, Golmohammadi S, Moradi Shahrebabak M, Sharafi Tafreshi Moghadam N, et al. The effect of berberine on obesity indices: a systematic review and meta-analysis. Int J Obes (Lond). 2026;50(1):53–73. doi:10.1038/s41366-025-01943-x · PubMed
  13. Wilding JPH, Batterham RL, Calanna S, Davies M, Van Gaal LF, Lingvay I, et al. Once-weekly semaglutide in adults with overweight or obesity. N Engl J Med. 2021;384(11):989–1002. doi:10.1056/NEJMoa2032183 · PubMed
  14. Guo Y, Chen Y, Tan ZR, Klaassen CD, Zhou HH. Repeated administration of berberine inhibits cytochromes P450 in humans. Eur J Clin Pharmacol. 2012;68(2):213–7. doi:10.1007/s00228-011-1108-2 · PubMed
  15. Chan E. Displacement of bilirubin from albumin by berberine. Biol Neonate. 1993;63(4):201–8. doi:10.1159/000243932 · PubMed
How this profile was checked

Last reviewed: 2026-10-23. All sources with a DOI or PMID were resolved automatically via Crossref or doi.org and PubMed.

Translated from the German profile (version of 2026-10-23); translation checked on 2026-10-26.

Checked

  • All abstracts read via PubMed; DOIs and PMIDs reconciled via PubMed esummary.
  • From the abstracts: AMPK, GLUT4, db/db mice and rats [1]; complex I, independent of LKB1/CaMKKβ [2]; LDLR mRNA 3.5-fold, protein 2.6-fold, 32 patients [3]; GLP-1 in rats and NCI-H716 [4]; 0.36%, liver/plasma 70-fold [5]; berberrubine [6]; n = 5, Cmax 0.4 ng/ml, conflict of interest NNB Nutrition [7]; n = 409, −0.99 vs. −0.59, R. bromii [8]; n = 36 and 48, HbA1c 9.5 to 7.5%, 34.5% gastrointestinal [9]; 46 studies, −0.73 [10]; 18 studies, 1788 people, LDL −0.46, TG −0.34, 83% China/Hong Kong [11]; 23 papers, −0.88 kg [12]; STEP 1 −14.9 vs. −2.4%, −12.7 kg [13]; CYP2D6 9-fold, 2C9 doubled, midazolam AUC +40% [14]; bilirubin displacement, advice against use in newborns and pregnant women [15].
  • In the full text (PMC4898966): 18 healthy Chinese men, 17 completed the study [14].
  • ClinicalTrials.gov: 134 entries for “berberine” (October 23, 2026).

Not verified

  • Legal status in Germany, the EU, and the USA.
  • Absolute bioavailability and half-life in humans.
  • Composition of the populations in the weight meta-analysis [12] (abstract only read).
  • Whether cases of kernicterus in newborns are causally documented (mentioned only as a report in the abstract of [15]).

No dosages, no sources of supply. This information does not replace medical advice.

Spotted an error or missing something?

Request a compound, suggest an improvement or report an error. Every message is read.

Type of message

The website stores nothing. The button opens your email app with a pre-filled message.