Guide
Who should not take berberine?
Berberine is contraindicated in pregnancy and nursing, and anyone under 18, on medication, or with a kidney or liver problem should check with a doctor first.
Our label directs against use if pregnant or nursing, and asks anyone under 18, taking medication, or with a medical condition to check with a doctor first. Below is why each of those cautions exists, and who else should ask before starting.
Pregnancy and breastfeeding
Do not use if pregnant or nursing. A laboratory and animal study found berberine displaces bilirubin from the protein that normally carries it in blood, about ten times more potently than a known reference compound — which is why berberine-containing herbs are specifically advised against in pregnancy and in jaundiced newborns. This caution applies at any dose, including our 73 mg serving.
Children
This product isn't formulated or dosed for children, and we give no dosing guidance for anyone under 18. Keep out of reach of children.
Kidney or liver problems
If you have a kidney or liver problem, ask a doctor before starting berberine. Berberine is processed by the body's drug-metabolizing enzymes and cleared partly through these organs, and how it behaves in someone with reduced kidney or liver function hasn't been studied at our dose.
If you have a heart-rhythm issue
If you have a heart-rhythm condition (such as a long QT interval or a slow heart rate), low blood pressure, or take a medication that affects heart rhythm, ask a doctor before starting berberine. A 2026 review of 22 studies documented QT-interval prolongation, slowed heart rate and low blood pressure as side effects in some cases, and a 2026 case report described a 92-year-old man who developed a dangerous heart rhythm about two weeks after starting a berberine supplement, which resolved when he stopped. These are uncommon, but they're the reason to check first. See berberine and the heart: what the research shows.
If you take medication
Berberine affects several of the enzymes and transporters the body uses to process other drugs, and it can add to the effect of medications that lower blood sugar. If you take any prescription medication, ask your doctor before adding berberine — see berberine and medications: what to check for specifics.
Questions people ask
Who should not take berberine?
Anyone pregnant or nursing (contraindicated), anyone under 18, and anyone with a kidney or liver problem or taking prescription medication should ask a doctor before starting.
Is berberine bad for kidneys?
We don't have research on berberine and kidney function at our 73 mg dose. If you have a kidney problem, ask a doctor before starting, since dosing guidance generally assumes normal organ function.
Can berberine cause liver problems?
We haven't found dedicated research on berberine and liver function at our dose. If you have a liver problem, check with a doctor before starting, for the same reason as above.
Who should take berberine?
Healthy adults who aren't pregnant or nursing, aren't under 18, and don't fall into the categories above may follow label directions — two capsules a day — after checking with a doctor if they take any medication.
Does berberine affect fertility?
We haven't found research on berberine and fertility at our 73 mg dose. If fertility is a concern, ask a doctor before starting any new supplement.
Is berberine safe for everyone?
No. It's contraindicated in pregnancy and nursing, and anyone under 18, on medication, or with a kidney or liver problem should ask a doctor before starting — see above for why each caution applies.
Does age change any of this?
Our label gives no dosing guidance for anyone under 18. For adults, we haven't found research specific to older age groups at our 73 mg dose; the same medication and organ-function cautions above still apply regardless of age.
Related reading: berberine and medications: what to check and berberine side effects.
Sources
- Displacement of bilirubin from albumin by berberine A laboratory and animal study found berberine displaces bilirubin from blood proteins, which is why it's advised against in pregnancy and in newborns.
- Berberine-Drug Interactions: Mechanisms, Clinical Relevance and Risk Stratification-A Narrative Review A 2026 review named barberry, Chinese goldthread and goldenseal as berberine's plant sources and found it can raise blood levels of some other drugs even though very little berberine itself reaches the bloodstream.
- Mechanistic Effects and Complications of Berberine on Cardiac Arrhythmias: A Systematic Review A 2026 systematic review of 22 studies found that alongside antiarrhythmic mechanisms in lab and animal models, berberine is documented to cause real cardiovascular side effects in some cases: QT-interval prolongation, slowed heart rate (bradycardia) and low blood pressure.
- Berberine Poisoning with Polymorphic Ventricular Tachycardia: A Case Report A 2026 case report describes a 92-year-old man who developed a life-threatening heart-rhythm abnormality (torsades de pointes) with a markedly prolonged QT interval about two weeks after starting a berberine supplement; his rhythm normalized after stopping it.
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
