Barberry: Benefits, Uses, Dosage, Fruit vs. Root & Side Effects

Barberry (Berberis vulgaris) is a thorny shrub whose tart red barberries are a staple of Persian cooking and whose root and bark carry berberine, the plant compound best known for supporting healthy blood sugar.129 Berberine is one of my go-to herbal tools for blood sugar and microbial cleansing,10 and the berries have trials of their own in people, where they lowered triglycerides, cholesterol and fasting blood sugar.3

Those three numbers often climb together because they share a root cause: when your body struggles to handle sugar and your liver starts storing fat instead of clearing it, triglycerides and blood sugar tend to rise, often with cholesterol, and that's where barberry's benefits cluster.3 Its sour berry and bitter root work on your digestion too, since sour and bitter flavors are some of the best cues for bile flow.1112

People have used barberry as medicine for more than 2,500 years, from Persia to Russia and across Europe,1 and the modern trials of the fruit, along with decades of research on berberine, keep landing where that long tradition pointed.39

Did you know?

• In Iran, dried barberries are called zereshk, and the shrub is grown around the eastern towns of Birjand and Qaen.1

• Dried purple-black barberries are close to a quarter fiber by weight: one lab analysis of the fruit used in a trial found 23.8 grams of fiber in 100 grams.7

• Indian barberry, a cousin species called daruharidra, is a classic Ayurvedic herb for the liver and for blood sugar.13

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What is barberry?

You'll also see it called common or European barberry, and in Spanish, agracejo. The shrub carries clusters of bright red berries that are so sour most people eat them dried and cooked rather than fresh, and its root and stem bark hold most of the plant's berberine, the bitter alkaloid behind much of its medicine.2 One of the trials on this page used seedless purple-black barberry, Berberis integerrima, a close relative grown in Iran.7

A few look-alike names cause confusion. Japanese barberry (Berberis thunbergii), a common garden shrub, is a different species from the one in the trials here. Bearberry is a different plant altogether, a low shrub whose leaves are used for the urinary tract, and our guide to bearberry (uva ursi) covers it.

Barberry nutrition

USDA doesn't keep a standard nutrient record for barberries, so the best numbers come from the trials themselves. In one lab analysis of the dried fruit used in a trial, 100 grams held 49.8 grams of carbohydrate, 23.8 grams of fiber, 7.7 grams of protein and 3.2 grams of fat, with a moisture content of 8.7%.7 That's a lot of fiber for a small, tart berry, and it's part of why a spoonful in your rice does more than add color.

The plant's active compounds include the alkaloids berberine, berbamine and palmatine, along with vitamin C, caffeic acid, pectin and tannins.1 The berries also carry anthocyanins, the red and purple pigments found in berries, and only a little of the root's alkaloid.2

A short history of barberry

Barberry's documented uses run wide: Russian practitioners used it for inflammation, high blood pressure and abnormal uterine bleeding, the dried root was taken to move bile, as a laxative and against diarrhea, and the fruit was used for painful periods, whooping cough and a sluggish liver.114 In Heal Your Cells, Dr. Will Cole and I describe how European herbalists prized barberry bark for liver and gallbladder support, and how healers on different continents, who never shared notes, settled on berberine-rich plants for the gut, the liver and the pancreas.10

Its cousin, Indian barberry (Berberis aristata), is a classic herb in Ayurvedic medicine, used for the liver and pancreas, skin infections, diabetes and inflamed eyes.13 Berberine-rich plants hold a place in Chinese medicine too, and berberine has been used for centuries in both traditions to support digestion and immunity.10

I've noticed that some patients respond far better to berberine than others. It's great for insulin, but in Chinese medicine it's also very cooling to the body, so for someone who already runs cold, I don't want to push their body cooler still.15 Barberry root holds most of the plant's berberine,2 so it brings that same cooling nature, which makes it a good match for someone who tends to run warm.

Barberry fruit vs. barberry root: which part does what?

The fruit and the root come from the same shrub, but you use them differently, and most of the human trials tested the fruit.32

If a label just says "barberry," check which part you're getting. Dried berries are a food, root and bark teas are the traditional herb, capsules may hold either fruit extract or root extract, and a berberine supplement is that one compound, concentrated. Oregon grape (Mahonia aquifolium, also called Berberis aquifolium) is barberry's close cousin, and you'll meet it in the skin section below.20

What is barberry good for?

How barberry works in your body

If your triglycerides and blood sugar have been creeping up and meals leave you feeling heavy, two things are often going on underneath: a liver that's holding on to fat, and digestion that isn't getting the cues it needs to handle the meal. Bile ties the two together, because your liver makes it and it works a bit like dish soap on the fat in your meal, and barberry works on that system, step by step, from the first taste onward:

Because barberry works on the digestion, the gut and the liver behind those numbers, the same plant shows up in trials for blood sugar, blood fats and fatty liver at once.

Barberry benefits

Barberry's benefits start with blood fats and blood sugar, where its trials are deepest, and reach from there to the liver, blood vessels, skin and digestion.

Does barberry lower blood sugar?

The clearest trial gave adults with type 2 diabetes six 500 mg capsules of dried barberry fruit extract a day, two at each meal, for 3 months. In this placebo-controlled trial, in which neither the people nor the researchers knew who got what, 47 people were randomized and 42 finished. Fasting blood sugar fell from 140.3 to 117 mg/dL on barberry and stayed level on placebo, going from 140.2 to 141, and HOMA-IR, a measure of insulin resistance, fell from 3.4 to 2.3. HbA1c went from 7.4% to 7.2%, a change that wasn't significant over those 3 months.5

Pooled across trials, barberry lowered blood sugar too: a 2025 review in adults with type 2 diabetes found fasting blood sugar 14.54 mg/dL lower across 7 randomized trials with 371 adults and HbA1c 0.65 points lower across 6 trials with 313 adults,23 and a 2024 review of 9 trials found, once the reviewers set aside outlying trials, fasting blood sugar 14.52 mg/dL lower and HbA1c 0.30 points lower.24 A third review, also from 2025, found no significant change in HbA1c across 4 trials with 188 adults.3 The juice works too: in an 8-week trial of 46 adults with type 2 diabetes (42 finished), in which people knew which group they were in, 200 mL (about 7 ounces) of barberry juice a day lowered fasting blood sugar, total cholesterol and blood pressure.26 Barberry root has one trial of its own, a placebo-controlled study of 88 adults with schizophrenia taking antipsychotic medicines, and it didn't prevent the weight gain those drugs cause;27 for blood sugar, the root's strength lies in its berberine.

Berberine, the root's main compound, has the deepest research of all. Across 31 randomized trials in type 2 diabetes, berberine, alone or added to diabetes medicines, lowered HbA1c by 0.63 points.9 It has also gone head to head with a drug: in a 3-month randomized pilot trial of 36 adults with newly diagnosed type 2 diabetes, 0.5 g of berberine hydrochloride three times a day lowered blood sugar about as well as the same dose of metformin, and HbA1c fell from 9.5% to 7.5% in the berberine group.28 In my Type 2 Diabetes Protocol, I call berberine the flagship, the most-studied natural tool for glucose,29 and in my Insulin Resistance & Prediabetes protocol it ranks first of the top 8 blood sugar supports, at 500 mg two or three times a day with meals.30

Barberry works best inside a plan that starts with food, movement and sleep, and our guides to the insulin resistance diet and normal blood sugar lay out the rest. To see where you stand, ask for fasting insulin along with your fasting glucose. The optimal range for fasting insulin is 2 to 8 µIU/mL.

Does barberry lower cholesterol and triglycerides?

Those pooled results come from a 2025 review of 6 randomized trials and 1 non-randomized study in people with metabolic syndrome and its risk factors, using barberry extract, dried fruit or juice, and the reviewers judged the blood-fat findings the most certain in the whole review.3 If your triglycerides run high, that's encouraging news, and our guide to high triglycerides covers the food side of bringing them down.

The single trials fill in the picture. In the diabetes trial above, triglycerides fell from 200.8 to 171.3 mg/dL and apoB, the protein that marks each LDL particle, fell from 128.1 to 111.2 mg/dL, while both rose slightly on placebo.5 That matters, because ApoB and ratios such as triglycerides to HDL say more about heart risk than LDL alone. In a placebo-controlled trial of 84 adults with high blood pressure, 10 grams of dried barberries a day for 8 weeks lowered triglycerides from 131.23 to 113.69 mg/dL, while they rose on placebo.7 Berberine lowers cholesterol on its own, too: in a review of placebo-controlled trials, it lowered LDL by about 18 mg/dL across 14 trials with 1,447 adults and triglycerides by about 30 mg/dL across 18 trials with 1,661 adults.18 Our list of cholesterol-lowering foods has more to pair with it.

Is barberry good for your liver?

Your liver sorts the fats and sugars from every meal, and when it's overloaded it starts storing fat in its own cells. I see this all the time in my practice: patients come in with an issue that's really liver-related, and it doesn't show up on their blood work for years.12 ALT and AST are the liver enzymes that leak into your blood when liver cells are under strain, so a drop in both is a good sign that the liver is settling down. Our guide to liver function explains the tests.

In the fatty liver trial, 99 adults with fatty liver on ultrasound and raised liver enzymes were enrolled, and 80 finished, 40 in each group. Taking two capsules of barberry extract a day, before breakfast and dinner, they saw ALT and AST each fall by roughly 40%, along with triglycerides, total cholesterol (from 211.40 to 186.05 mg/dL) and about 1.5 kg (about 3 pounds) of weight. On placebo, triglycerides went from 214.7 to 201.47 mg/dL, a change that wasn't significant.4

That fits what tradition saw in the plant. The dried root was taken to move bile and for the liver,1 and European herbalists prized barberry bark for liver and gallbladder support.10 Bile flow is part of how your liver clears out what it's finished with, and sour foods help it along: as I've said on my show, a little lemon juice in your water or apple cider vinegar is very supportive for the liver, gallbladder and bile.12 A spoonful of tart barberries belongs in that same family of sour foods.

Barberry for your heart and blood vessels

That trial gave adults already taking blood pressure medicine either dried purple-black barberries or a placebo for 8 weeks, without telling them which they were getting; 78 of the 84 finished. Flow-mediated dilation, a measure of how well an artery widens when blood flow picks up, improved 6.54 percentage points more on barberry, and two markers of inflammation in the artery wall, ICAM-1 and MCP-1, fell.16 Systolic blood pressure over 24 hours came down compared with placebo,25 and CRP, the inflammation marker, fell from 2.64 to 1.95 mg/L while it held at 2.34 to 2.30 on placebo.7

Blood pressure came down in other trials too: the barberry juice trial in type 2 diabetes lowered systolic and diastolic pressure,26 and the 2025 review pooled 3 trials with 202 people and found systolic pressure 9.84 mmHg and diastolic 11.31 mmHg lower, a result the reviewers rated low certainty.3 An earlier 2021 review of 5 trials with 350 people found no significant drop.31 The guide to natural ways to lower blood pressure covers the food and lifestyle steps to pair with it.

Barberry also helps with the oxidative stress that runs alongside metabolic syndrome. In a 6-week placebo-controlled trial of 106 adults with metabolic syndrome, in which neither the people nor the researchers knew who got what, 600 mg of dried barberry capsules a day lowered the pro-oxidant-antioxidant balance, a blood measure of free-radical stress, while placebo didn't.6 In the diabetes trial, total antioxidant capacity rose from 805 to 925.6 µmol/L.5

Barberry for acne and skin

Barberry fruit can help clear acne. In a 4-week placebo-controlled trial of 49 teenagers aged 12 to 17 with moderate to severe acne, 25 on barberry and 24 on placebo, 600 mg a day of an extract of the dried fruit cut total lesions by about 45%, inflamed and non-inflamed lesions alike, while the changes on placebo weren't significant, and no notable side effects came up.17 It pairs well with the other home remedies for acne.

The 10% cream often linked with barberry for psoriasis is made from Oregon grape, barberry's close cousin. In a 12-week placebo-controlled trial of 200 adults with mild to moderate psoriasis, a 10% Oregon grape cream applied twice a day improved psoriasis scores and quality of life, with side effects such as a rash or burning in under 1% of people.32 A review of the cream's trials found significant improvement in 5 of 7 psoriasis trials.20

Barberry for digestion and gut health

Barberry root works on digestion the way other digestive bitters do. As I've explained on my show, when your body tastes bitter, it starts to release more bile, stomach acid and enzymes, and bitter foods help heal your liver and your gallbladder and really support your entire body, especially your metabolism.11 Our guide to bitter foods has others to add to your plate.

Barberry's use against diarrhea is backed by berberine's own trial. In 165 adults with acute diarrhea from E. coli or cholera, a single 400 mg dose of berberine sulfate stopped diarrhea within 24 hours in 42% of the E. coli patients, against 20% in the comparison group, with no side effects noted.19 Pair it with the other steps for stopping diarrhea.

The same compound helps restore microbial balance in the gut. Berberine, which comes from barberry root, is the first herbal antimicrobial in my SIBO Protocol,33 and SIBO, small intestinal bacterial overgrowth, is exactly that kind of imbalance in the small intestine. In a review of 104 patients at one gastroenterology practice, where patients chose their own treatment, herbal formulas that included berberine-containing herbs cleared SIBO on a breath test in 46% of people, against 34% on rifaximin, the usual antibiotic, so the herbs did about as well as the drug.34 Our guide to goldenseal, another berberine-rich root, covers its gut uses.

How to use barberry: dried berries, tea, extract and capsules

Food comes first for me, so start with the berries: the 10-gram trial used plain dried barberries, the same ones you'd cook with.7 The extracts and the root are there when you want a stronger dose or the traditional bitter herb.

To make a root tea, steep cut dried barberry root or bark in hot water, using the amount on the package, then strain it and sip it before a meal, so the bitterness reaches your tongue first. Capsules skip your tongue, while tea and tincture let you taste the bitterness that starts your digestion.11 Whatever form you choose, check the label for the part of the plant and the milligrams of extract per capsule, so you can match the form and amount above.

How to cook with dried barberries (zereshk)

Dried barberries are an everyday food in Iran,15 where they're best known cooked into rice, and their bright, sour taste works anywhere you'd use dried cranberries or a squeeze of lemon. A few kitchen tips help: rinse them and pick out any stems, soak them briefly in cool water to plump them, and cook them only for a minute or two, because their natural sugars scorch fast.

Because barberries are so tart, a little honey goes a long way toward balancing a dish, and raw local honey or Manuka works well.

Barberry side effects and who should skip it

Pregnancy, breastfeeding and newborns. Keep barberry root, bark and berberine products out of pregnancy and breastfeeding, and never give them to a baby. In lab and rat studies, berberine pushed bilirubin off the protein that carries it in the blood, the step that puts jaundiced newborns at risk, and reviewers advise caution in pregnancy and avoiding it while nursing.378 In a 2025 case-control study of 150 children with birth defects and 150 without, in Iran's main barberry-growing region, mothers who recalled eating more than a tablespoon of barberries a day during pregnancy had higher odds of a child with a birth defect; that shows a link, not a cause.38 So if you're pregnant, enjoy barberries cooked into rice, keep them to a tablespoon or less a day and confirm that amount with your OB.

At the amounts studied. Side effects in the barberry trials were few and mild, mostly loose stools in the first week: 3 cases of mild diarrhea and 1 of constipation among the 40 people on extract in the liver trial, and 2 cases of mild diarrhea in the dried-berry trial.47 Concentrated berberine upsets the stomach more often, in 2% to 23% of people in its cholesterol trials,18 so take extracts with meals and start with the lower dose. If you have G6PD deficiency, stick to the berries in food.8

Stop and get checked if stomach pain or diarrhea doesn't settle, and see a doctor right away if a baby's skin or the whites of the eyes turn yellow.

The bottom line

Barberry: frequently asked questions

References

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2. Imenshahidi M, Hosseinzadeh H. Berberine and barberry (Berberis vulgaris): A clinical review. Phytother Res. 2019;33(3):504-523. doi:10.1002/ptr.6252. PMID:30637820
3. Zhang X, Lou Q, Liou S, Wang X. The effect of barberry supplementation on components of metabolic syndrome: a grade assessment systematic review and meta-analysis of randomized controlled trials. J Health Popul Nutr. 2025;44(1):313. doi:10.1186/s41043-025-01067-y. PMID:40886028
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7. Emamat H, Zahedmehr A, Asadian S, Nasrollahzadeh J. The effect of barberry (Berberis integerrima) on lipid profile and systemic inflammation in subjects with cardiovascular risk factors: a randomized controlled trial. BMC Complement Med Ther. 2022;22(1):59. doi:10.1186/s12906-022-03539-8. PMID:35255880
8. Rad SZK, Rameshrad M, Hosseinzadeh H. Toxicology effects of Berberis vulgaris (barberry) and its active constituent, berberine: a review. Iran J Basic Med Sci. 2017;20(5):516-529. PMCID:PMC5478780. PMID:28656087
9. Xie W, Su F, Wang G, Peng Z, Xu Y, Zhang Y, et al. Glucose-lowering effect of berberine on type 2 diabetes: A systematic review and meta-analysis. Front Pharmacol. 2022;13:1015045. doi:10.3389/fphar.2022.1015045. PMID:36467075
10. Axe J, Cole W. Heal Your Cells. Avery; 2026. ISBN 9798217181353 (European herbalists and barberry bark for liver and gallbladder support; berberine as a go-to herbal tool for blood sugar and microbial cleansing, sourced from plants such as barberry, goldenseal and Oregon grape, and used for centuries in Chinese and Ayurvedic medicine to support digestion and immunity).
11. Axe J. 10 Biblical Superfoods That Can Add Years to Your Life. The Dr. Josh Axe Show, Ep. 393. 2026 (bitter taste and the release of bile, acid and enzymes, at 25:38; bitter foods for the liver, gallbladder and metabolism, at 27:11; bitter and sour flavors and sweet cravings, at 27:52; YouTube: https://www.youtube.com/watch?v=9AnNi1umufc&t=1538s).
12. Axe J. Hidden Signs Your Liver Is Sluggish (And What To Do Before It Becomes Serious). The Dr. Josh Axe Show. 2026 (liver problems that don't show up on blood work for years, at 1:46; sour foods, bile flow and the liver and gallbladder, at 34:24; YouTube: https://www.youtube.com/watch?v=PiOaEva8EBc&t=106s).
13. Marchelak A, Gieleta M, Krasocka W, Magiera A. Berberis aristata DC. (Indian barberry): Current insight into botanical, phytochemical, and pharmacological aspects, pharmacokinetics, safety of use and modern therapeutic applications. Fitoterapia. 2025;183:106539. doi:10.1016/j.fitote.2025.106539. PMID:40239774
14. Imanshahidi M, Hosseinzadeh H. Pharmacological and therapeutic effects of Berberis vulgaris and its active constituent, berberine. Phytother Res. 2008;22(8):999-1012. doi:10.1002/ptr.2399. PMID:18618524
15. Axe J, Buhler B. The Testosterone, Weight Loss & Hormone Lies Your Doctor Never Told You | Brigham Buhler. The Dr. Josh Axe Show. 2026 (Dr. Axe on patients' differing response to berberine, at 26:48; berberine as great for insulin but very cooling to the body in Chinese medicine, at 26:57; not pushing a patient whose body already runs cold cooler still, at 27:10; YouTube: https://www.youtube.com/watch?v=Sx-sxJmzO_M&t=1608s).
16. Emamat H, Asadian S, Zahedmehr A, Ghanavati M, Nasrollahzadeh J. The effect of barberry (Berberis vulgaris) consumption on flow-mediated dilation and inflammatory biomarkers in patients with hypertension: A randomized controlled trial. Phytother Res. 2021;35(5):2607-2615. doi:10.1002/ptr.7000. PMID:33350540
17. Fouladi RF. Aqueous extract of dried fruit of Berberis vulgaris L. in acne vulgaris, a clinical trial. J Diet Suppl. 2012;9(4):253-61. doi:10.3109/19390211.2012.726702. PMID:23038982
18. 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):403-427. doi:10.1007/s40265-023-01841-4. PMID:36941490
19. Rabbani GH, Butler T, Knight J, Sanyal SC, Alam K. Randomized controlled trial of berberine sulfate therapy for diarrhea due to enterotoxigenic Escherichia coli and Vibrio cholerae. J Infect Dis. 1987;155(5):979-84. doi:10.1093/infdis/155.5.979. PMID:3549923
20. Janeczek M, Moy L, Lake EP, Swan J. Review of the Efficacy and Safety of Topical Mahonia aquifolium for the Treatment of Psoriasis and Atopic Dermatitis. J Clin Aesthet Dermatol. 2018;11(12):42-47. PMID:30666279
21. Yu Y, Hao G, Zhang Q, Hua W, Wang M, Zhou W, et al. Berberine induces GLP-1 secretion through activation of bitter taste receptor pathways. Biochem Pharmacol. 2015;97(2):173-7. doi:10.1016/j.bcp.2015.07.012. PMID:26206195
22. 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. PMID:33024120
23. Musazadeh V, Hamidi N, Noormohammadi M, Shidfar F. The Effect of Berberis (Vulgaris and Integerrima) on Cardiovascular Risk Factors in Patients With Type 2 Diabetes Mellitus: A Systematic Review, Meta-Analysis, and GRADE Assessment. Curr Ther Res Clin Exp. 2025;102:100788. doi:10.1016/j.curtheres.2025.100788. PMID:40502989
24. Hussain HU, Ali E, Tanveer A, Ismail SM, Furqan H, Ahsan MN, et al. Efficacy of Berberis vulgaris and Berberis integerrima on glycemic indices and weight profile in type 2 diabetic patients: A systematic review and meta-analysis of randomized controlled trials. J Ayurveda Integr Med. 2024;15(5):101039. doi:10.1016/j.jaim.2024.101039. PMID:39413550
25. Emamat H, Zahedmehr A, Asadian S, Nasrollahzadeh J. The effect of purple-black barberry (Berberis integerrima) on blood pressure in subjects with cardiovascular risk factors: a randomized controlled trial. J Ethnopharmacol. 2022;289:115097. doi:10.1016/j.jep.2022.115097. PMID:35150818
26. Lazavi F, Mirmiran P, Sohrab G, Nikpayam O, Angoorani P, Hedayati M. The barberry juice effects on metabolic factors and oxidative stress in patients with type 2 diabetes: A randomized clinical trial. Complement Ther Clin Pract. 2018;31:170-174. doi:10.1016/j.ctcp.2018.01.009. PMID:29705451
27. Rostami H, Babaali F, Moradi L, Golfakhrabadi F, Abdi L. Evaluation of the Effect of Barberry Root (Berberis Vulgaris) on the Prevention of Metabolic Syndrome Caused by Atypical Antipsychotic Drugs in Patients with Schizophrenia: A Three-Blind Placebo-Controlled Clinical Trial. Iran J Psychiatry. 2023;18(3):362-368. doi:10.18502/ijps.v18i3.13015. PMID:37575603
28. 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. PMID:18442638
29. Axe J. The Type 2 Diabetes Protocol. DrAxe.com protocol; 2026 (berberine as the flagship, the most-studied natural tool for glucose, 500 mg two to three times before meals, p. 15).
30. Axe J. Insulin Resistance & Prediabetes. DrAxe.com protocol; 2026 (Top 8 blood sugar supports, berberine ranked first at 500 mg two to three times daily with meals, p. 18).
31. Atefi M, Ghavami A, Hadi A, Askari G. The effect of barberry (Berberis vulgaris L.) supplementation on blood pressure: A systematic review and meta-analysis of the randomized controlled trials. Complement Ther Med. 2021;56:102608. doi:10.1016/j.ctim.2020.102608. PMID:33197673
32. Bernstein S, Donsky H, Gulliver W, Hamilton D, Nobel S, Norman R. Treatment of mild to moderate psoriasis with Reliéva, a Mahonia aquifolium extract--a double-blind, placebo-controlled study. Am J Ther. 2006;13(2):121-6. doi:10.1097/00045391-200603000-00007. PMID:16645428
33. Axe J. The SIBO Protocol. DrAxe.com protocol; 2026 (Top 8 SIBO remedies, berberine ranked first).
34. Chedid V, Dhalla S, Clarke JO, Roland BC, Dunbar KB, Koh J, et al. Herbal therapy is equivalent to rifaximin for the treatment of small intestinal bacterial overgrowth. Glob Adv Health Med. 2014;3(3):16-24. doi:10.7453/gahmj.2014.019. PMID:24891990
35. 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. PMID:21870106
36. Wu X, Li Q, Xin H, Yu A, Zhong M. Effects of berberine on the blood concentration of cyclosporin A in renal transplanted recipients: clinical and pharmacokinetic study. Eur J Clin Pharmacol. 2005;61(8):567-72. doi:10.1007/s00228-005-0952-3. PMID:16133554
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38. Najafi E, Nejad MEM, Bazyar H, Moghaddam HR, Nasiri K, Aghamohammadi V, et al. The relationship between the maternal consumption of barberry, saffron, pickled vegetables, and tea and the odds of congenital anomalies in Iranian children under 10 years of age: A case-control study. J Educ Health Promot. 2025;14:258. doi:10.4103/jehp.jehp_180_24. PMID:40772092

Dr. Josh Axe, DC, DNM, CNS

Doctor of Natural Medicine · Founder, DrAxe.com

Dr. Axe is a certified doctor of natural medicine, clinical nutritionist, and multiple New York Times bestselling author. He has spent 20+ years in clinical practice helping people heal at the root cause and founded one of the most-visited natural-health platforms in the world.

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