Eyebright Drug Interactions, Uses, Effectiveness, Safety & More
What is this page for?
First and foremost: how Eyebright interacts with medications. The heart of this page is the interaction list — every drug Eyebright is known to interact with, and how serious each one is.
But these pages have grown well beyond that into a full monograph — what Eyebright is, what people use it for and how strong the evidence is, its safety and side effects, and answers to the questions we’re asked most — written and reviewed by the clinical staff at HelloPharmacist. It’s educational information from our licensed clinical databases, not medical advice, and we don’t sell or endorse products. Our editorial policy
Check Eyebright against your medication
Add one medicationEyebright Drug Interactions: The Bottom Line
From the HelloPharmacist Editorial Team · Updated July 2026Based on the available evidence, the overall risk of a clinically significant Eyebright drug interaction appears low for most people. None of the listed interactions are rated major, and every one traces back to a single theoretical concern rather than documented problems in people.
The one area worth watching is diabetes medications, including insulin and other drugs that lower blood sugar. Animal research suggests eyebright may reduce blood glucose on its own, so in theory adding it could push blood sugar lower than expected. Because blood sugar is a closely monitored target, people managing diabetes should be aware of this possibility, even though it has not been confirmed in human studies.
Although the list of interacting medications looks long, it reflects this one blood-sugar concern applied across the many drugs used to treat diabetes. The evidence comes from animal research only, so the effect is possible but not established, and no harmful combinations have been documented in people. A long list here signals caution in one area, not broad danger.
Based on HelloPharmacist’s Eyebright interaction data and reviewed under our editorial standards.
Drugs that interact with Eyebright
86 medications have a known interaction with Eyebright, graded by severity. Select any drug for the full evidence-based detail.
Don’t want to scroll the list? Just ask.
Tell us the medications you take and we’ll check each one against Eyebright using our pharmacist-reviewed interaction data.
AI summaries are generated from our Eyebright interaction data for education only — always confirm with your pharmacist. How we use AI
No drugs match “”.
What Severity, Likelihood & Evidence Mean
Severity — How Serious It Can Be
- Major. Clinically significant; generally best avoided, or used only under direct professional supervision.
- Moderate. May need monitoring, a dose adjustment, or separating the times you take each one.
- Minor. Generally not clinically significant, but still worth noting and mentioning to your pharmacist.
- No known interaction. Checked against our sources with nothing documented — not the same as proven safety.
Likelihood — How Well It’s Documented
- Likely. Well-controlled human studies have demonstrated the likely existence of this interaction
- Probable. Interaction 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.
- Possible. 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
- Unlikely. Interaction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Where This Data Comes From
- Interaction records are evidence-graded and sourced from the Natural Medicines database (TRC Healthcare), the same reference used by pharmacists and hospitals.
- Each drug listed above links to the full report for that exact Eyebright combination — clinical detail, likelihood, evidence level, and citations.
- Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.
The kinds of drugs Eyebright affects
Every type of medication (drug category) Eyebright is known to interact with. Open any category for the detail — or search your exact drug in the checker above.
Antidiabetes Drugs
Theoretically, eyebright might increase the risk of hypoglycemia when taken with antidiabetes drugs.
Animal research suggests that eyebright lowers blood glucose levels.
Eyebright: Uses, Safety & Side Effects
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.

- Scientific name
- Euphrasia officinalis
- Family
- Orobanchaceae
- Part used
- Aerial parts (leaves, stems, and flowers)
- Common forms
- Tea, eye drops, tincture, capsules, homeopathic preparations, compresses
- Eye irritation and redness
- Conjunctivitis (pink eye)
- Eye strain
- Allergy and cold-related eye symptoms
- Nasal congestion and hay fever
Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.
Likely safe in small amounts as a tea, but using homemade or non-sterile preparations directly in the eye is risky.
Insufficient reliable information available; avoid using.
Read the full pregnancy detailInsufficient reliable information available; avoid using.
Read the full breastfeeding detailPregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center). Safety guidance is general; always confirm with your pharmacist or doctor for your situation.
Overview
Eyebright is a small flowering plant that grows wild in meadows and grassy areas across Europe and parts of Asia. Its name comes from its long history of being used for eye complaints. The plant is semi-parasitic, meaning it draws some nutrients from the roots of nearby grasses.
The parts used in herbal products are the above-ground portions — the leaves, stems, and flowers. These contain natural compounds such as flavonoids, tannins, and iridoid glycosides (including aucubin). People have used eyebright as a tea, a compress, eye drops, or a tincture, mainly for irritated or watery eyes and for allergy and cold symptoms.
How it works
The proposed activity of eyebright is usually credited to its tannins, which have an astringent (tightening) effect, and to flavonoids and iridoid glycosides, which may have mild anti-inflammatory and antioxidant effects in the laboratory.
These mechanisms could, in theory, soothe irritated tissue or reduce inflammation. However, most of this research has been done in test tubes or animals, not in well-controlled human studies. Because of this, we cannot be certain how — or whether — eyebright works in people.
Does Eyebright work?
How to read these evidence grades
Natural Medicines’ 7-point scale. We show each rating’s label word-for-word.
For Eyebright, current evidence isn’t strong enough to rate any specific use. The conditions it has been studied for are listed below.
Also studied for 9 conditions — evidence insufficient to rate
Insufficient Reliable Evidence To Rate Allergic rhinitis (hay fever)
Although there has been interest in using oral eyebright for allergic rhinitis, there is insufficient reliable information about the clinical effects of eyebright for this purpose.
Insufficient Reliable Evidence To Rate Asthenopia (eye strain)
Although there has been interest in using topical eyebright for asthenopia, there is insufficient reliable information about the clinical effects of eyebright for this purpose.
Insufficient Reliable Evidence To Rate Blepharitis
Although there has been interest in using topical eyebright for blepharitis, there is insufficient reliable information about the clinical effects of eyebright for this purpose.
Insufficient Reliable Evidence To Rate Cancer
Although there has been interest in using oral eyebright for cancer, there is insufficient reliable information about the clinical effects of eyebright for this purpose.
Insufficient Reliable Evidence To Rate Common cold
Although there has been interest in using oral eyebright for the common cold, there is insufficient reliable information about the clinical effects of eyebright for this purpose.
Insufficient Reliable Evidence To Rate Conjunctivitis
It is unclear if topical eyebright eye drops are beneficial in patients with conjunctivitis.
Insufficient Reliable Evidence To Rate Cough
Although there has been interest in using oral eyebright for cough, there is insufficient reliable information about the clinical effects of eyebright for this purpose.
Insufficient Reliable Evidence To Rate Pharyngitis
Although there has been interest in using oral eyebright for pharyngitis, there is insufficient reliable information about the clinical effects of eyebright for this purpose.
Insufficient Reliable Evidence To Rate Rhinosinusitis
Although there has been interest in using oral eyebright for rhinosinusitis, there is insufficient reliable information about the clinical effects of eyebright for this purpose.
Source & disclaimer. Effectiveness ratings and evidence summaries are provided by Natural Medicines (Therapeutic Research Center) and shown as licensed. Where Natural Medicines hasn’t rated a use, HelloPharmacist’s pharmacists may add their own reviewed rating and evidence (each such entry is labeled). This is educational information, not medical advice — talk with your pharmacist or doctor before starting, stopping, or changing a supplement.
Safety & precautions
Eyebright taken as a tea in small amounts is generally considered low-risk for most adults, but solid safety data are limited. The bigger concern is putting eyebright preparations directly into the eye. Homemade or non-sterile drops and washes can introduce bacteria or other contaminants and cause a serious eye infection. The eye is very sensitive, so never put anything in it that is not sterile and intended for ophthalmic use.
Pregnancy and breastfeeding: Because there is not enough reliable safety information, eyebright should be avoided during pregnancy and while breastfeeding.
People with eye conditions, contact lens wearers, and those with allergies to plants in this family should be especially cautious. Always check with a pharmacist or doctor before using eyebright, especially in or around the eyes.
Side effects
When taken by mouth, eyebright may cause mild side effects such as nausea, stomach upset, or headache in some people. Allergic reactions are possible, particularly in people sensitive to related plants.
When applied to the eye, eyebright can cause stinging, redness, itching, watering, increased eye pressure, or vision changes. The most serious risk is eye infection from non-sterile preparations. Stop use and seek care if you notice eye pain, swelling, discharge, or worsening symptoms.
Eyebright: Reported Adverse Effects
Documented safety reports on Eyebright from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.
Reports by conditionCluster headache Neurologic/CNS
Orally, eyebright has been reported to cause confusion and headache.
- Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Constipation Gastrointestinal
Orally, eyebright has been reported to cause nausea and constipation.
- Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Cough Pulmonary/Respiratory
Orally, eyebright has been reported to cause cough, dyspnea, and nasal congestion.
- Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
Pruritus Ocular/Otic
Topically, eyebright has been reported to cause increased ocular pressure, lacrimation, pruritus, redness, swelling of eyelid margins, vision changes, and photophobia when applied to the eyes. Ophthalmic eyebright products should be used with caution due to the potential for contamination.
- Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
- Wichtl MW. Herbal Drugs and Phytopharmaceuticals. Ed. N.M. Bisset. Stuttgart: Medpharm GmbH Scientific Publishers, 1994.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
Adverse-effects data: Natural Medicines, Therapeutic Research Center
Dosing
There is no standardized or well-established dose for eyebright. Traditional use as a tea typically involves steeping the dried herb in hot water, but amounts vary widely between products and sources.
If you choose to use a commercial eyebright product, follow the directions on the label and choose products from reputable manufacturers. For anything used in or near the eye, only use products that are specifically made and labeled as sterile eye preparations. When in doubt, ask your pharmacist for guidance before starting.
Eyebright & Pregnancy
Eyebright & Breastfeeding
© 2026 Therapeutic Research Center
Pregnancy & lactation ratings: Natural Medicines, Therapeutic Research Center
References & further reading
The 4 references that drive our Eyebright monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.
- Newall CA, Anderson LA, Philpson JD. Herbal Medicine: A Guide for Healthcare Professionals. London, UK: The Pharmaceutical Press, 1996.
- Wichtl MW. Herbal Drugs and Phytopharmaceuticals. Ed. N.M. Bisset. Stuttgart: Medpharm GmbH Scientific Publishers, 1994.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: John Wiley & Sons, 1996.
- Porchezhian, E., Ansari, S. H., and Shreedharan, N. K. Antihyperglycemic activity of Euphrasia officinale leaves. Fitoterapia 2000;71(5):522-526. PubMed
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.
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
Brands that make products with Eyebright
150 brands in our database make a supplement containing Eyebright.
Supplement products with Eyebright
505 products in our database contain Eyebright. Open any to see its full ingredient list and every drug interaction we check.
Eyebright: Common Questions
What is Eyebright used for, and does it work?
Does Eyebright interact with prescription medications?
How are Eyebright interactions rated?
Is it safe to take Eyebright with my medications?
Where does this Eyebright interaction information come from?
What is Eyebright used for?
Does Eyebright actually work?
Is it safe to put Eyebright in my eyes?
Can I use Eyebright if I'm pregnant or breastfeeding?
Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy
Products that contain Eyebright
A rotating sample of real supplements in our database that list Eyebright — open any to see its full ingredients and every drug interaction we check.
- Eyebright Extract Powder by Herbadiet
- E&E-B by Pure Herbs
- Quercetin Strength by MegaFood
- Bilberry Eyebright Extract by Oregon's Wild Harvest
- Eyebright Alcohol Free by Herbal Terra
- Eye Health Tincture by Doctor Morse's Healing Herbs
- Vision by Oweli
- Eyebright Herb 430 mg by Swanson Premium Brand
- GO-W by Pure Herbs
- Alle-Relief by Eclectic Herb
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