Research summary
Berberine Side Effects
Quick answer
Berberine is a substance found in plants including goldenseal, barberry and Oregon grape. Human trials commonly report gastrointestinal side effects. NCCIH cautions about medication interactions, including cyclosporine, and possible harm during pregnancy or breastfeeding; it considers berberine likely unsafe for infants.[1], [2]
What does the evidence support?
Read each finding with its qualification. These are source-supported statements, not a ranking of products or personal treatment advice.
| Finding and qualification | References |
|---|---|
| Berberine is a substance found in plants including goldenseal, barberry and Oregon grape. This describes plant occurrence, not evidence that a supplement improves a health outcome. | [1] |
| In an umbrella review of meta-analyses of randomized controlled trials in adults, the most commonly reported side effects of oral berberine were gastrointestinal symptoms, including constipation and diarrhea. These findings concern gastrointestinal adverse effects reported in the umbrella review; they do not establish safety during pregnancy or breastfeeding, with other medications, at a particular dose, or with long-term use. | [2] |
| Berberine may interact with medicines, including cyclosporine. NCCIH advises people taking medicine to speak with their health care provider before considering berberine supplements. This is a medication-interaction caution, not advice to stop, replace or change a prescribed medicine. | [1] |
| NCCIH cautions that berberine is likely unsafe for infants and may also be unsafe during pregnancy or breastfeeding because of possible effects on the fetus or infant. This caution concerns infants, pregnancy and breastfeeding; the cited guidance links berberine exposure to harmful bilirubin buildup in infants. | [1] |
Gastrointestinal symptoms are the most commonly reported side effects
An umbrella review of meta-analyses of randomized controlled trials reported that the most commonly reported side effects of oral berberine were gastrointestinal symptoms, including constipation and diarrhea.[2]
Liver-enzyme findings in pooled trials
A meta-analysis of 12 randomized controlled trials found that berberine supplementation did not significantly change alanine aminotransferase or aspartate aminotransferase compared with control. This is a pooled group-average result and does not establish individual safety.[3]
Limits of the current evidence
The umbrella review concluded that the methodological quality of pooled berberine meta-analyses needs improvement and that clinical effects should be confirmed in high-quality randomized controlled trials. This is an evidence-quality limitation, not a finding about a specific adverse effect or dose.[2]
Medication and vulnerable-population cautions
Berberine may interact with medicines, including cyclosporine. NCCIH advises people taking medicine to speak with their health care provider before considering berberine supplements. This is a medication-interaction caution, not advice to stop, replace or change a prescribed medicine.[1]
NCCIH cautions that berberine is likely unsafe for infants and may also be unsafe during pregnancy or breastfeeding because of possible effects on the fetus or infant. This caution concerns infants, pregnancy and breastfeeding; the cited guidance links berberine exposure to harmful bilirubin buildup in infants.[1]
Can a reassuring liver test mean a supplement is safe for everyone?
No. The pooled liver-enzyme result describes group averages in 12 trials. It cannot rule out an individual reaction, a drug interaction, or a risk in a population not represented. Gastrointestinal symptoms such as constipation and diarrhea were the most commonly reported effects in the umbrella review, but reported frequency is not a complete long-term safety assessment.[2], [3]
The pregnancy, breastfeeding, and infant cautions are a separate reason to avoid generalizing adult tolerability. NCCIH links infant exposure to potentially harmful bilirubin buildup and advises caution around pregnancy and breastfeeding. For someone taking medicines, including cyclosporine, a clinician or pharmacist review should precede use; an interaction warning is not an instruction to alter the prescribed drug.[1]
References
- Berberine and Weight Loss: What You Need To Know. NIH National Center for Complementary and Integrative Health. Retrieved 2026-09-09. Government health fact sheet View source →
- Berberine and health outcomes: An umbrella review.. Phytotherapy research : PTR. 2023. Systematic review View source →
- The effect of berberine supplementation on obesity parameters, inflammation and liver function enzymes: A systematic review and meta-analysis of randomized controlled trials.. Clinical nutrition ESPEN. 2020. Systematic review and meta-analysis View source →
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