Drug & supplement interaction

Eyebright + Tobutamide

Tobutamide brand name: Mobenol.

Moderate Interaction
Medically reviewed by · Updated September 2026
The bottom line Moderate

Eyebright has a moderate interaction with Tobutamide. Theoretically, eyebright 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

Eyebright and Tobutamide

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

Moderate

ANTIDIABETES DRUGS

Why this applies to Tobutamide

Tobutamide falls under ANTIDIABETES DRUGS — the group Eyebright interacts with.

Theoretically, eyebright might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that eyebright lowers blood glucose levels.
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

Tolbutamide (Mobenol) is an older sulfonylurea that lowers your blood sugar by nudging your pancreas to release more insulin. On its own, it can sometimes push blood sugar too low. The concern here is that eyebright, in animal studies, also appeared to bring blood sugar down. Stack the two together and, in theory, you could end up with hypoglycemia, which might show up as shakiness, sweating, a racing heart, confusion, or feeling lightheaded.

I want to be honest about the evidence though: this is based on lab and animal research, not real people, so it's a theoretical caution rather than something we see often. Still, if you take tolbutamide and want to try eyebright, check with your pharmacist or doctor first and keep an eye on your readings.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Porchezhian, E., Ansari, S. H., and Shreedharan, N. K. Antihyperglycemic activity of Euphrasia officinale leaves. Fitoterapia 2000;71(5):522-526. 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

Eyebright Also Interacts With Other Medications

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

Moderate 85 No known interaction 2,745 (incl. Tobutamide)
Taking anything else?

Check Another of Your Medications Against Eyebright

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

Everything else you take

See Every Supplement That Interacts With Tobutamide

This page covers Eyebright only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Tobutamide page lists 256 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 · 215 moderate · 39 minor.

From our pharmacist’s overview on the Tobutamide page

“Long as this list is, it mostly tells one story, and with Tobutamide (Mobenol), a sulfonylurea that lowers blood sugar in type 2 diabetes, that story deserves genuine care. Most of the 215 moderate entries add to the drug's effect and invite hypoglycemia, the shaky, sweaty, sometimes dangerous low.”

Reviewed by 2 · Jul 18, 2026

Open the Tobutamide interaction page

One more smart check

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

We hold 504 real supplement products containing Eyebright, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Eyebright. Your product may carry other ingredients that interact with Tobutamide too, on top of Eyebright — 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 Eyebright and Tobutamide 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 Eyebright
Top half

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

29 days ago today
Medication Tobutamide
Steady interest

#2,180 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 Eyebright

What is Eyebright?

Eyebright
  • Eye irritation and redness
  • Conjunctivitis (pink eye)
  • Eye strain
  • Allergy and cold-related eye symptoms
  • Nasal congestion and hay fever

Eyebright is a traditional herb long used for minor eye irritation, redness, and allergy symptoms, but high-quality human studies are very limited. There is not enough reliable evidence to confirm it works, and using non-sterile herbal preparations in the eye carries a real risk of infection, so talk to your pharmacist or doctor before trying it.

Read the full Eyebright monograph & all interactions
Keep checking

Other Drugs & Eyebright

Browse every other medication we’ve checked against Eyebright — 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
85 Moderate 2,744 No interaction
Moderate

85 interactions

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

No interaction 2,744 drugs checked — show the list

We also checked Eyebright against these medications and found no known interaction in our sources. Open any page to confirm.

Showing the 60 most looked-up of 2,744 medications checked with no known interaction — see the full Eyebright list.

See the full Eyebright interactions page
See every supplement checked against Tobutamide, ranked by severity
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

Keep exploring
Eyebright monograph › Uses, safety, and every drug interaction in one place Tobutamide supplement interactions › Every supplement checked against Tobutamide, ranked by severity Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Eyebright and Tobutamide Together: Common Questions

Can you take Eyebright with Tobutamide?
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 Eyebright and Tobutamide 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 Tobutamide and Eyebright?

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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.