Drug & supplement interaction

Collard + Acarbose

Acarbose brand names: Precose, Prandase, Glucobay.

Moderate Interaction
The bottom line Moderate

Collard has a moderate interaction with Acarbose. In an animal study, an aqueous extract of collard leaves and stems has been shown to reduce glucose levels.

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

Collard and Acarbose

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

Moderate

ANTIDIABETES DRUGS

Why this applies to Acarbose

Acarbose falls under ANTIDIABETES DRUGS — the group Collard interacts with.

In an animal study, an aqueous extract of collard leaves and stems has been shown to reduce glucose levels. Collard extract 60 mg/kg lowers blood glucose levels in a rat model of diabetes after both single- and multi-dose oral administration similarly to glibenclamide 5 mg/kg. Theoretically, collard extract might have additive effects when used concomitantly with antidiabetes drugs and may increase the risk of hypoglycemia. Monitor blood glucose levels closely. Dose adjustments may be necessary. Some antidiabetes drugs include glimepiride (Amaryl), glyburide (DiaBeta, Glynase PresTab, Micronase), insulin, pioglitazone (Actos), rosiglitazone (Avandia), chlorpropamide (Diabinese), glipizide (Glucotrol), and tolbutamide (Orinase).
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: in a rat study, a concentrated extract of collard greens lowered blood sugar about as much as a diabetes pill. The thinking is that if you pair a strong collard supplement with acarbose, the two could work together and push your blood sugar lower than you intend. With acarbose, that mainly shows up as numbers that drift low, and acarbose can also cause gas, bloating, and loose stools that might feel worse if you're not eating consistently.

I want to be honest about the evidence, though. This is based only on an animal study, so it's pretty weak, and eating collard greens as a normal food is very unlikely to cause trouble. Concentrated capsules are the bigger question mark. If you start one, keep an eye on your sugar readings and check in with your pharmacist or doctor before changing anything.

References
  1. Amssayef A, Eddouks M. Antihyperglycemic Effect of the Moroccan Collard Green (Brassica oleracea var. viridis) in Streptozotocin-Induced Diabetic Rats. Endocr Metab Immune Disord Drug Targets 2020. PubMed

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

Collard Also Interacts With Other Medications

Collard has 85 moderate known drug interactions in our database — the Acarbose 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 Collard

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

From our Q&A

Questions About Collard or Acarbose

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Collard or Acarbose, 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 Acarbose

This page covers Collard only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Acarbose page lists 281 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Siberian Cocklebur (major), Wine (major) and Acai (moderate).

By severity: 4 major · 240 moderate · 37 minor.

From our pharmacist’s overview on the Acarbose page

“Acarbose (Precose, Glucobay) is taken with meals to blunt the blood sugar rise after eating, and its supplement list calls for genuine care, starting with the four major-rated entries: heavy alcohol and the herb Siberian cocklebur can strain the liver alongside acarbose, while activated charcoal can soak up oral drugs and cut what reac…”

Reviewed by 2 · Jul 18, 2026

Open the Acarbose interaction page

One more smart check

Taking Collard as Part of a Dietary Supplement Product? Check It for Interactions

We hold 379 real supplement products containing Collard, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Collard. Your product may carry other ingredients that interact with Acarbose too, on top of Collard — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Collard and Acarbose 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 Collard
Top half

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

29 days ago today
Medication Acarbose
Steady interest

#1,608 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 Collard

What is Collard?

  • General nutrition and vitamin source
  • Bone health
  • Heart health support
  • Digestive fiber
  • Antioxidant intake

Collard is a leafy green vegetable in the cabbage family that is rich in vitamins, minerals, and fiber, and is best thought of as a nutritious food rather than a medicine. Eating it as part of a balanced diet is healthy for most people, but there is little high-quality research on collard as a concentrated supplement. If you take blood thinners or have kidney concerns, talk with your pharmacist or doctor because of its vitamin K and oxalate content.

Read the full Collard monograph & all interactions
Medication

About Acarbose

What Is Acarbose Used For?

Brand names: Precose, Prandase, Glucobay

Acarbose tablets are used to help control blood sugar in adults with type 2 diabetes. They are always used together with a proper diet and regular exercise — not as a replacement for them.

Acarbose can be used on its own or combined with other diabetes medicines such as sulfonylureas, insulin, or metformin to get better blood sugar control.

See full Acarbose drug information
Keep checking

Other Drugs & Collard

Browse every other medication we’ve checked against Collard — 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 Collard 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 Collard and Acarbose Together: Common Questions

Can you take Collard with Acarbose?
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 Collard and Acarbose 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 Acarbose and Collard?

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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.