Drug & supplement interaction

Phaseolus Vulgaris + Metformin

Metformin brand names: Glucophage, Metformin.

Moderate Interaction
The bottom line Moderate

Phaseolus Vulgaris has a moderate interaction with Metformin. Theoretically, Phaseolus vulgaris might increase the risk of hypoglycemia when taken with antidiabetes drugs.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Phaseolus Vulgaris and Metformin

Here is the interaction we found between these two, with the evidence behind it.

Moderate

ANTIDIABETES DRUGS

Why this applies to Metformin

Metformin falls under ANTIDIABETES DRUGS — the group Phaseolus Vulgaris interacts with.

Theoretically, Phaseolus vulgaris might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Small clinical studies suggest that Phaseolus vulgaris beans or bean pods, ingested alone or along with white mulberry leaf and bilberry, reduce blood glucose levels in some patients with diabetes.
Severity Moderate Likelihood Possible Evidence D

Interaction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the gist if you're taking metformin and thinking about a white bean (Phaseolus vulgaris) 'carb blocker.' Metformin already works partly by lowering how much sugar your body absorbs and makes. The bean extract slows starch digestion too, so in theory the two could stack up and push your blood sugar a little lower than expected. That could mean signs of low blood sugar (hypoglycemia) like shakiness, sweating, dizziness, or feeling foggy.

I want to be honest about the strength here: this is mostly theoretical and based on small or anecdotal reports, not strong proof. Eating beans as food is generally fine. If you want to try a concentrated supplement, check with your pharmacist or doctor first and keep an eye on your sugar readings.

References
  1. Tjokroprawiro A, Pikir BS, Budhiarta AA, et al. Metabolic effects of onion and green beans on diabetic patients. Tohoku J Exp Med 1983;141 Suppl:671-6. PubMed
  2. Boivin M, Flourie B, Rizza RA, Go VL, DiMagno EP. Gastrointestinal and metabolic effects of amylase inhibition in diabetics. Gastroenterology. 1988;94(2):387-94. PubMed
  3. Ionescu-Tirgoviste, C., Popa, E., Mirodon, Z., Simionescu, M., and Mincu, I. [The effect of a plant mixture on the metabolic equilibrium in patients with type-2 diabetes mellitus]. Rev.Med Interna Neurol.Psihiatr.Neurochir.Dermatovenerol.Med Interna 1989

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction has not been documented in well-controlled studies, however, the interaction has been demonstrated in some small human studies or in controlled animal studies in conjunction with multiple case reports.
  • PossibleInteraction has been documented in animal or in lab research, or the interaction has been documented in humans but is limited to case reports or conflicting clinical research exists.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Phaseolus Vulgaris Also Interacts With Other Medications

Phaseolus Vulgaris has 85 moderate known drug interactions in our database — the Metformin one above is one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Phaseolus Vulgaris

Covers the 2,830 medications we’ve checked against Phaseolus Vulgaris. Pick one to open its full report.

From our Q&A

Questions About Phaseolus Vulgaris or Metformin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Phaseolus Vulgaris or Metformin, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Metformin

This page covers Phaseolus Vulgaris only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Metformin page lists 258 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Siberian Cocklebur (major), Acai (moderate), African Wild Potato (moderate) and Agaricus Mushroom (moderate).

By severity: 2 major · 217 moderate · 39 minor.

From our pharmacist’s overview on the Metformin page

“Siberian cocklebur is the ingredient I most want anyone taking metformin (Glucophage) to know about. It has caused severe low blood sugar in people, documented in humans, and it should not be combined with any glucose-lowering medication.”

Reviewed by 2 · Jul 18, 2026

Open the Metformin interaction page

How much people look this up

Where Phaseolus Vulgaris and Metformin Sit Against Everything Else

Out of every supplement and medication people look up on HelloPharmacist, here is where these two land this week — and which way each has been moving.

Supplement Phaseolus Vulgaris
Steady interest

#1,196 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Metformin
Top 5%

#30 of 2,830 medications looked up here in the last 7 days

29 days ago today

Position among everything looked up on this site, not a measure of how commonly either one is used or how important it is. A supplement can climb this list because of a news story. It counts every request to the page, automated ones included, and nothing here identifies anyone.

Supplement

About Phaseolus Vulgaris

What is Phaseolus Vulgaris?

  • Weight management
  • Carbohydrate ('starch') blocking
  • Blood sugar support
  • General nutrition and fiber

Phaseolus vulgaris, the common bean, is widely eaten as food, and a concentrated white bean extract is marketed as a 'carb blocker' for weight loss. Some small studies suggest it may modestly reduce starch digestion, but the evidence for meaningful weight loss is limited and mixed. Talk to your pharmacist or doctor before using it as a supplement, and remember beans must be cooked thoroughly because raw or undercooked beans can be toxic.

Read the full Phaseolus Vulgaris monograph & all interactions
Medication

About Metformin

What Is Metformin Used For?

Brand names: Glucophage, Metformin

Metformin is used to improve blood sugar (glucose) control in people with type 2 diabetes mellitus. It is always used together with diet and exercise, not instead of them.

Metformin hydrochloride tablets and oral solution are approved for adults and children 10 years and older. Metformin hydrochloride extended-release tablets — including brands such as Fortamet, Glumetza, and Metformin Hydrochloride Extended Release — are approved for adults only.

See full Metformin drug information
Keep checking

Other Drugs & Phaseolus Vulgaris

Browse every other medication we’ve checked against Phaseolus Vulgaris — both the ones with a known interaction and the ones without. Select any drug for the full detail.

0Major
85Moderate
0Minor
2,744No known interaction
Moderate

85 interactions

Showing 60 of 85 moderate interactions — see all 85 on the Phaseolus Vulgaris page.

No interaction 2,744 drugs checked — show the list
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

Parts of this content are provided by the Therapeutic Research Center, LLC.

DISCLAIMER: Currently this does not check for drug-drug interactions. This is not an all-inclusive comprehensive list of potential interactions and is for informational purposes only. Not all interactions are known or well-reported in the scientific literature, and new interactions are continually being reported. Input is needed from a qualified healthcare provider including a pharmacist before starting any therapy. Application of clinical judgment is necessary.

© 2021 Therapeutic Research Center, LLC

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Pharmacist Counseling Corner

Taking Phaseolus Vulgaris and Metformin Together: Common Questions

Can you take Phaseolus Vulgaris with Metformin?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Phaseolus Vulgaris and Metformin interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Metformin and Phaseolus Vulgaris?

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This information is for education only and is not a substitute for professional medical advice. Always check with your pharmacist or doctor before starting, stopping, or combining supplements and medications.