The formula
GlycoBarrier ingredients: all six, read from the panel
Six ingredients share one 121 mg line on the Supplement Facts panel. This page takes each one in the order the panel lists it, says what it is, quotes what a source we actually opened says about it, and prints the caution that comes with it. One of the six carries no citation, and we say so on that one rather than reaching for a weaker source.
The blend is listed in descending order of weight, so gotu kola is the largest single part of it and grape seed the smallest. No other quantity is published. Two of the six — horse chestnut and butcher’s broom — have the strongest clinical support here and are absent from the brand’s marketing artwork. Not one of the six has a glucose indication.
What a proprietary blend hides
The FDA permits a manufacturer to group ingredients under a blend name and publish one combined weight. The trade-off, from the buyer's side, is total: you learn the sum and lose every part. The one rule that survives is that the ingredients inside the blend must be listed in descending order of predominance by weight.
This matters more here than in most products, because 121 mg is a small number to begin with. Divide it six ways and the average share is about twenty milligrams. Four of the six ingredients below are studied at doses larger than the entire blend, which means at most one or two of them can be anywhere near a researched intake — and the label does not tell you which.
1. Gotu Kola Extract — Centella asiatica, leaf
Gotu kola is listed first, so under US labelling rules it is the largest single share of the 121 mg blend. It is a traditional vein and wound-healing herb, and it is the ingredient whose presence in a circulation formula makes the most sense. Memorial Sloan Kettering is blunt about the size of the evidence: "Only a few studies suggest that gotu kola may be helpful for wound healing or poor circulation. Larger studies that confirm such results are needed." Its monograph adds that "only a few studies have been conducted in humans" and that although some data suggest gotu kola can decrease venous pressure in people with venous insufficiency, "there is insufficient evidence to support its use for any of these conditions."
Typical amount in research: Human studies are few; oral trials typically use 60-180 mg a day of a standardised extract. Amount in GlycoBarrier: not published.
Caution. MSK lists skin rash and liver toxicity among reported adverse effects, and warns that lab studies suggest gotu kola may increase the risk of side effects of CYP450 substrate drugs, with the clinical relevance not yet determined.
Sources. Memorial Sloan Kettering Cancer Center, About Herbs (2026). Gotu Kola.
2. Chinese Hawthorn Extract — Crataegus species, fruit
Hawthorn has the largest research file of anything on this label, and it is still an unsettled one. Memorial Sloan Kettering's summary is that "hawthorn may be helpful in some patients with heart failure" while "definitive data are needed on safety and efficacy", and on blood pressure that "data are conflicting. More research is needed." NCCIH is firmer: "There is conflicting evidence on the effects of hawthorn in people with heart failure," and "there isn't enough evidence to know whether hawthorn affects heart disease, angina, abnormal heartbeat, or the buildup of plaque in arteries." Note also that this label specifies the fruit, while most hawthorn trials use a leaf-and-flower extract.
Typical amount in research: Heart-failure trials commonly use 160-1800 mg a day of a standardised leaf-and-flower extract. Amount in GlycoBarrier: not published.
Caution. MSK says not to take hawthorn if you are pregnant or taking antiplatelets or anticoagulants, and lists dizziness as the most common side effect, with low blood pressure and irregular heartbeat on overdose. NCCIH separately warns that some products sold as hawthorn have been found to contain toxic yellow oleander, which "may cause severe harm or even be fatal", and that no study has tested whether hawthorn is safe beyond 16 weeks.
Sources. Memorial Sloan Kettering Cancer Center, About Herbs (2026). Hawthorn. Also: NCCIH, National Institutes of Health (2026). Hawthorn: Usefulness and Safety.
3. Horse Chestnut Extract — Aesculus hippocastanum, seed
Horse chestnut is not named anywhere on the brand's marketing artwork, and it is arguably the most important ingredient in the bottle. MSK's summary is that "horse chestnut may help treat chronic venous insufficiency, but its long-term effects are not known", and that "several clinical trials support the use of horse chestnut as short-term treatment for chronic venous insufficiency" while long-term effects remain unknown. On varicose veins specifically it is flat: "this claim is not backed by any evidence."
Typical amount in research: Trials use 300-600 mg a day of a seed extract standardised to 50-150 mg of aescin. Amount in GlycoBarrier: not published.
Caution. MSK states that "horse chestnut seeds are toxic, and can cause major stomach irritation, vomiting, muscle twitching, incoordination, redness, facial swelling, and other serious conditions" — properly processed extracts remove the toxic component, and no processing information is published for this product. It also documents a life-threatening kidney rupture, heart inflammation in a 32-year-old man, and several intestinal obstructions requiring surgery, and warns that horse chestnut products containing aesculin may increase bleeding risk with warfarin, aspirin or other blood thinners.
Sources. Memorial Sloan Kettering Cancer Center, About Herbs (2026). Horse Chestnut.
4. Motherwort Extract — Leonurus cardiaca, aerial parts
Motherwort is a traditional European herb for palpitations and anxiety, and it is the one ingredient on this label for which we found no usable reference. We searched the NIH Office of Dietary Supplements, NCCIH and Memorial Sloan Kettering's About Herbs database — the three sources this site cites throughout — and none of them holds a monograph on it. Rather than substitute a supplement retailer, a content farm or a journal abstract we are not qualified to appraise, we have left this ingredient without a citation and said so.
Typical amount in research: No reliable dose range could be sourced from the references this site uses. Amount in GlycoBarrier: not published.
Caution. No citable safety file means no quantified safety information, which is not the same as an absence of risk. Motherwort is traditionally avoided in pregnancy and is generally described as having sedative and cardiac activity, so it belongs in the conversation with a clinician alongside anything you take for your heart.
Source. None. We searched NIH, NCCIH and Memorial Sloan Kettering — the three references this site uses — and found no monograph on this ingredient we could link. Rather than substitute a supplement retailer or a content farm, we leave this line empty and tell you it is empty.
5. Butcher's Broom Extract — Ruscus aculeatus, root
Butcher's broom is the second ingredient on this label that the marketing does not name, and the one that produces the sharpest finding on this site. Memorial Sloan Kettering describes it as "a shrub whose extracts are widely used to treat varicose veins, hemorrhoids, and lymphedema", and reports that "small clinical studies have shown that products containing butcher's broom can help improve the symptoms of chronic venous insufficiency, but the long-term safety and effectiveness of these products are not known."
Typical amount in research: Vein trials commonly use 150-300 mg a day of extract, often combined with hesperidin and vitamin C. Amount in GlycoBarrier: not published.
Caution. MSK carries an explicit Do Not Take line: "You have diabetes (butcher's broom was reported to cause diabetic ketoacidosis, characterized by high levels of compounds called ketones in the blood.)" The case it cites is a 39-year-old woman with diabetes, five days after taking butcher's broom for mild ankle swelling. Diarrhoea and skin reactions are also reported.
Sources. Memorial Sloan Kettering Cancer Center, About Herbs (2026). Butcher's Broom.
6. Grape Seed Extract — Vitis vinifera, seed
Grape seed is listed last, so under the descending-weight rule it is the smallest share of the 121 mg blend. Memorial Sloan Kettering lists its studied uses as lowering high cholesterol, reducing inflammation and treating atherosclerosis, and notes that "grape seed extract has other uses, but doctors have not studied them to see if they work." NCCIH reports that grape seed extract "may have desirable effects on levels of low-density lipoprotein (LDL) cholesterol and triglycerides but not on total cholesterol", and that it "reduced diastolic blood pressure… but not systolic blood pressure". Neither body's page addresses venous circulation or leg swelling at all.
Typical amount in research: Trials commonly use 100-300 mg a day. Amount in GlycoBarrier: not published.
Caution. MSK advises talking to a healthcare provider if you take blood thinners such as warfarin, because "grape seed extract may increase your risk of bleeding", and notes in vitro antiplatelet activity plus inhibition of CYP3A4 and modulation of UGT enzymes. NCCIH describes it as generally well tolerated.
Sources. Memorial Sloan Kettering Cancer Center, About Herbs (2026). Grape Seed. Also: NCCIH, National Institutes of Health (2026). Grape Seed Extract: Usefulness and Safety.
The two the marketing leaves out
The brand's own ingredient panel names four botanicals. The Supplement Facts panel names six. The two extra are horse chestnut and butcher's broom — and on the evidence they are the two most interesting things in the bottle.
Why leave out your two best ingredients?
We have no idea, and we are not going to invent a motive. What we can say is that horse chestnut has several clinical trials supporting short-term use in chronic venous insufficiency, and butcher's broom has small clinical studies showing symptom improvement in the same condition. Those are the two strongest evidence claims available to this formula, and neither appears on the artwork.
The uncharitable reading is that both also carry the most specific warnings of the six: horse chestnut's toxic raw seed and bleeding risk, and butcher's broom's diabetes contraindication. The charitable reading is that the panel was designed before the formula was finalised. Either way, a buyer reading only the marketing does not know what is in the bottle.
Note also what the same panel is headlined: “Liquid Drops straight from nature”, over a product whose other-ingredients line includes sodium benzoate, potassium sorbate and sucralose.
Where the evidence actually is
If you strip this label down to the ingredients with published human research relevant to the reason the product is sold — circulation, not glucose — you are left with three, and two of them are the ones the marketing does not name.
The three with real vein research
- Horse chestnut. MSK: “several clinical trials support the use of horse chestnut as short-term treatment for chronic venous insufficiency”, with long-term effects unknown.
- Butcher’s broom. MSK: “small clinical studies have shown that products containing butcher’s broom can help improve the symptoms of chronic venous insufficiency”.
- Gotu kola. MSK: some data suggest it “can decrease venous pressure in people with venous insufficiency”, though there is “insufficient evidence to support its use for any of these conditions”.
- All three are listed on the panel with a plant part specified, which is better practice than many liquid formulas manage.
The three that need explaining
- Hawthorn is a heart herb, not a vein herb, and its trials use a leaf-and-flower extract while this label specifies fruit.
- Grape seed is studied for cholesterol and blood pressure. Neither MSK nor NCCIH addresses venous circulation in its monograph.
- Motherwort has no monograph at NIH, NCCIH or MSK at all, so nothing about it can be checked.
- And the whole blend is 121 mg, which is below the trial dose of four of the six on its own.
That is the honest shape of this formula: three ingredients that belong in a vein product, one heart herb, one antioxidant extract, one unknown — and a total weight that cannot deliver a researched dose of any of them. The how-it-works page goes through the proposed mechanisms one at a time.
- Memorial Sloan Kettering Cancer Center, About Herbs (2026). Hawthorn.
- Memorial Sloan Kettering Cancer Center, About Herbs (2026). Horse Chestnut.
- Memorial Sloan Kettering Cancer Center, About Herbs (2026). Butcher's Broom.
- Memorial Sloan Kettering Cancer Center, About Herbs (2026). Grape Seed.
- Memorial Sloan Kettering Cancer Center, About Herbs (2026). Gotu Kola.
- NCCIH, National Institutes of Health (2026). Hawthorn: Usefulness and Safety.
- NCCIH, National Institutes of Health (2026). Grape Seed Extract: Usefulness and Safety.
- U.S. Food and Drug Administration (2026). Questions and Answers on Dietary Supplements.
- U.S. Food and Drug Administration (2026). Dietary Supplement Labeling Guide.
How we chose which sources to cite
Three bodies, and one rule about what happens when none of them has a page.
Memorial Sloan Kettering, About Herbs
A cancer centre's herb monographs, maintained for clinicians dealing with patients who take supplements alongside treatment. The best single source for interactions anywhere, and the source of five of the six citations on this page.
NCCIH
The National Center for Complementary and Integrative Health, part of NIH. Its herb pages are written for the public and are unusually direct about uncertainty. It supplied the hawthorn and grape seed corroborations here.
NIH Office of Dietary Supplements
The US government's own fact sheets on supplement ingredients, written for health professionals. Blunt, current and unsentimental about negative findings.
And the rule: if none of those three has a page on an ingredient, we say so and publish no citation. We do not substitute a supplement retailer's blog, an aggregator or a journal abstract we cannot evaluate. Motherwort falls into that category on this label, and its section says so in plain words.
This is a stricter standard than most sites apply and it has a visible cost: one ingredient with a blank where a source should be. We think a visible blank is more honest than a link that looks authoritative and is not.
Two things worth knowing about extracts
Both apply to every ingredient on this label, and neither is published for any of them.
The ratio decides the dose
A 10:1 extract means ten parts of raw herb produced one part of extract. Thirty milligrams of a 10:1 extract corresponds to 300 mg of herb. Without the ratio, the word “extract” on a label carries no quantitative meaning at all — it could be a concentrate or it could be finely ground herb.
For horse chestnut, the figure is aescin
This is the most important unpublished number on the whole product. Trials specify 50 to 150 mg of aescin a day, and properly processed extracts are standardised to a stated percentage. The same processing removes esculin, the fraction MSK associates with the raw seed's toxicity. One figure would answer both the efficacy question and the safety question, and it is not there.
When a manufacturer has paid for standardisation, it says so, because it is the most valuable thing it can print. The absence of a ratio on all six ingredients here is not proof that none is standardised. It means you cannot tell, which for a buying decision amounts to the same thing.
Read the panel first, then decide
A 60 ml dropper bottle, 30 servings, one 121 mg blend of six botanicals and no individual amounts. The live price and the return terms are both shown on the seller’s checkout screen.
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