Drug & supplement interaction

Oregon Grape + Oxytetracycline , Polymyxin B

Oxytetracycline , Polymyxin B brand name: Terak.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Oregon Grape and Oxytetracycline , Polymyxin B in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Oregon Grape and Oxytetracycline , Polymyxin B

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Oxytetracycline , Polymyxin B and Oregon Grape in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Oregon Grape safety at a glance

Oregon Grape overall Use caution Topical use appears generally well tolerated, but oral use is less well studied and should be approached carefully.
Pregnancy Likely Unsafe When used orally. Berberine, a constituent of Oregon grape, is thought to cross the placenta and may cause harm to the fetus. Kernicterus has developed in newbo... Read the full pregnancy detail
Breastfeeding Likely Unsafe When used orally. Berberine and other harmful constituents can be transferred to the infant through breast milk. Read the full breastfeeding detail

Pregnancy & breastfeeding ratings are from Natural Medicines (Therapeutic Research Center) — the full detail is in the Special populations card below. Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Oxytetracycline , Polymyxin B and Oregon Grape? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Oxytetracycline , Polymyxin B

Interactions in our licensed database are recorded against drug classes, not just single drug names. Oxytetracycline , Polymyxin B is filed under a single classification — photosensitizing drugs. Oregon Grape has documented interactions with 9 drug classes — the most serious being anticoagulant/antiplatelet drugs (moderate), antidiabetes drugs (moderate) and antihypertensive drugs (moderate) — and none of Oxytetracycline , Polymyxin B’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Oregon Grape Does Interact With Other Medications

Oregon Grape has 1,218 moderate known drug interactions in our database — Oxytetracycline , Polymyxin B isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Oregon Grape

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

What to actually watch for

What Oregon Grape Itself Has Been Linked To

This is not an interaction — nothing below involves Oxytetracycline , Polymyxin B. It is the side-effect record for Oregon Grape on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Oregon Grape, this list is the first place to look.

  • Itching Additional detail

    “Topically, Oregon grape may cause itching, burning, and skin irritation in some patients.”

    Oregon Grape · Natural Medicines adverse-effect record, reported in skin irritation.

    2 sources cited
    1. 854. Wiesenauer M, Lydtke R. Mahonia aquifolium in patients with Psoriasis vulgaris; an intraindividual study. Phytomedicine 1996;3:231-5.
    2. 14000. Gulliver WP, Donsky HJ. A report on three recent clinical trials using Mahonia aquifolium 10% topical cream and a review of the worldwide clinical experience with Mahonia aquifolium for the treatment of plaque psoriasis. Am J Ther 2005;12:398-406. PubMed

Everything above comes from the Natural Medicines adverse-effect record for Oregon Grape — expand a row for the licensed statement it rests on. We haven’t matched Oxytetracycline , Polymyxin B to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Oxytetracycline , Polymyxin B.

Special populations

Oregon Grape in Pregnancy & Breastfeeding

Pregnancy Likely Unsafe

When used orally. Berberine, a constituent of Oregon grape, is thought to cross the placenta and may cause harm to the fetus. Kernicterus has developed in newborn infants exposed to berberine.

Lactation Likely Unsafe

When used orally. Berberine and other harmful constituents can be transferred to the infant through breast milk.

DISCLAIMER: This tool is intended for informational purposes only, and should not be interpreted as specific medical advice. Patients should consult with a qualified healthcare provider before making decisions about therapies and/or health conditions.© 2026 Therapeutic Research Center

Everything else you take

See Every Supplement That Interacts With Oxytetracycline , Polymyxin B

This page covers Oregon Grape only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Oxytetracycline , Polymyxin B page lists 20 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Alfalfa (moderate), Angelica Archangelica (moderate), Arrach (moderate), Bergamot (moderate) and Bishop's Weed (moderate).

By severity: 19 moderate · 1 minor.

From our pharmacist’s overview on the Oxytetracycline , Polymyxin B page

“St. John's wort is the entry I'd check first for anyone using Terak (oxytetracycline with polymyxin B), since both the herb and this antibiotic's tetracycline component can make skin react more strongly to sunlight.”

Reviewed by 2 · Jul 18, 2026

Open the Oxytetracycline , Polymyxin B interaction page

One more smart check

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

We hold 740 real supplement products containing Oregon Grape, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Oregon Grape. Even though Oregon Grape itself has no known interaction with Oxytetracycline , Polymyxin B, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Oregon Grape and Oxytetracycline , Polymyxin B 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 Oregon Grape
Top 25%

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

29 days ago today
Medication Oxytetracycline , Polymyxin B
Top half

#754 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Oregon Grape reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Oregon Grape and Oxytetracycline , Polymyxin B records this page draws on were last updated July 11, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Oregon Grape

What is Oregon Grape?

Oregon Grape
  • Psoriasis (topical)
  • Eczema and other skin conditions
  • Digestive upset
  • Mild skin infections
  • General 'detox' or tonic use

Oregon grape is a shrub whose root contains berberine and related compounds. The strongest (though still modest) evidence is for topical creams that may slightly ease psoriasis; evidence for other uses is limited. Talk with your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Mahonia aquifolium · Berberidaceae · Root and root bark (sometimes stem bark); berries are used in food · Topical creams and ointments, tinctures, capsules, dried root extract

An interaction check asks whether these two react with each other — it does not ask whether Oregon Grape is a good idea for someone in your situation. Here is what our Oregon Grape record says about it on its own.

Oregon Grape: dosing

There is no official, well-established standard dose for Oregon grape. Topical products are usually applied as directed on the label, often once or twice daily to the affected skin area.For tinctures and capsules, follow the manufacturer's instructions, since the amount of active compounds varies from product to product.

From our Oregon Grape monograph — the full record covers uses, side effects and every documented interaction.

Read the full Oregon Grape monograph & all interactions
Keep checking

Other Drugs & Oregon Grape

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

0Major
1,218Moderate
0Minor
1,611No known interaction
Moderate

1,218 interactions

Showing 60 of 1,218 moderate interactions — see all 1,218 on the Oregon Grape page.

No interaction 1,611 drugs checked — show the list
Evidence & sources

Oregon Grape References

The 21 references that drive our Oregon Grape 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.

  1. Wiesenauer M, Lydtke R. Mahonia aquifolium in patients with Psoriasis vulgaris; an intraindividual study. Phytomedicine 1996;3:231-5.
  2. Chan E. Displacement of bilirubin from albumin by berberine. Biol Neonate 1993;63:201-8. PubMed
  3. Janbaz KH, Gilani AH. Studies on preventive and curative effects of berberine on chemical-induced hepatotoxicity in rodents. Fitoterapia 2000;71:25-33.. PubMed
  4. Wu X, Li Q, Xin H, Yu A, Zhong M. Effects of berberine on the blood concentration of cyclosporin A in renal transplanted recipients: clinical and pharmacokinetic study. Eur J Clin Pharmacol 2005;61:567-72. PubMed
  5. Gulliver WP, Donsky HJ. A report on three recent clinical trials using Mahonia aquifolium 10% topical cream and a review of the worldwide clinical experience with Mahonia aquifolium for the treatment of plaque psoriasis. Am J Ther 2005;12:398-406. PubMed
  6. Zhang Y, Li X, Zou D, et al. Treatment of type 2 diabetes and dyslipidemia with the natural plant alkaloid berberine. J Clin Endocrinol Metab 2008;93:2559-65. PubMed
  7. Budzinski JW, Foster BC, Vandenhoek S, Arnason JT. An in vitro evaluation of human cytochrome P450 3A4 inhibition by selected commercial herbal extracts and tinctures. Phytomedicine 2000;7:273-82. PubMed
  8. Chatterjee P, Franklin MR. Human cytochrome p450 inhibition and metabolic-intermediate complex formation by goldenseal extract and its methylenedioxyphenyl components. Drug Metab Dispos 2003;31:1391-7. PubMed
  9. Shanbhag, S. M., Kulkarni, H. J., and Gaitonde, B. B. Pharmacological actions of berberine on the central nervous system. Jpn.J Pharmacol 1970;20(4):482-487. PubMed
  10. Wu, J. F. and Liu, T. P. [Effects of berberine on platelet aggregation and plasma levels of TXB2 and 6-keto-PGF1 alpha in rats with reversible middle cerebral artery occlusion]. Yao Xue.Xue.Bao. 1995;30(2):98-102.
  11. Peng, W. H., Hsieh, M. T., and Wu, C. R. Effect of long-term administration of berberine on scopolamine-induced amnesia in rats. Jpn J Pharmacol 1997;74(3):261-266. DOI
  12. Sabir M and Bhide NK. Study of some pharmacological actions of berberine. Ind J Physiol & Pharmac 1971;15(3):111-132.
  13. Tripathi YB and Shukla SD. Berberis artistata inhibits PAF induced aggregation of rabbit platelets. Phytotherapy Research 1996;10:628-630.
  14. Yin, J., Xing, H., and Ye, J. Efficacy of berberine in patients with type 2 diabetes mellitus. Metabolism 2008;57(5):712-717. PubMed
  15. Zhang, H., Wei, J., Xue, R., Wu, J. D., Zhao, W., Wang, Z. Z., Wang, S. K., Zhou, Z. X., Song, D. Q., Wang, Y. M., Pan, H. N., Kong, W. J., and Jiang, J. D. Berberine lowers blood glucose in type 2 diabetes mellitus patients through increasing insulin re

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Oregon Grape and Oxytetracycline , Polymyxin B Together: Common Questions

Is it safe to take Oregon Grape with Oxytetracycline , Polymyxin B?
We do not list a known interaction between Oregon Grape and Oxytetracycline , Polymyxin B. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Oregon Grape and Oxytetracycline , Polymyxin B combination checked?
Interactions in our licensed database are recorded against drug classes. Oxytetracycline , Polymyxin B is filed under 1 classification, and Oregon Grape has documented interactions with 9 drug classes — none of Oxytetracycline , Polymyxin B's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Oregon Grape interact with any other medications?
Yes. Oregon Grape has 1,218 documented drug interactions in our database — Oxytetracycline , Polymyxin B is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Oxytetracycline , Polymyxin B interact with any supplements?
Yes. Oxytetracycline , Polymyxin B has documented interactions with 20 supplements in our database — Oregon Grape is not one of them. The Oxytetracycline , Polymyxin B interaction page linked on this page lists every one, ranked by severity.

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

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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.