Drug & supplement interaction

Phellodendron + Doxycyline

Doxycyline brand name: Doxychel.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Oct 4, 2026
The bottom line No known interaction

We found no known interaction between Phellodendron and Doxycyline 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. Additionally, although there is no interaction, the label for Doxycyline states a food rule worth keeping to, and the two are separately associated with some of the same side effects, which would make a new symptom harder to attribute to one or the other.

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Interaction report

Phellodendron and Doxycyline

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 Doxycyline and Phellodendron 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.

Phellodendron safety at a glance

Phellodendron overall Use caution Generally used short-term in traditional medicine, but human safety data are limited.
Pregnancy Avoid Berberine-containing herbs may not be safe in pregnancy, so avoid use.
Breastfeeding Likely Unsafe When used orally. The berberine constituent of phellodendron 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 Doxycyline and Phellodendron? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Doxycyline

Interactions in our licensed database are recorded against drug classes, not just single drug names. Doxycyline is filed under 8 classifications — including tetracycline antibiotics, antibiotic drugs, p-glycoprotein substrates. Phellodendron has documented interactions with 14 drug classes — the most serious being anticoagulant/antiplatelet drugs (moderate), antidiabetes drugs (moderate) and antihypertensive drugs (moderate) — and none of Doxycyline’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

Phellodendron Does Interact With Other Medications

Phellodendron has 1,162 moderate known drug interactions in our database — Doxycyline isn’t one of them. If you take anything else, check it against the full list below.

Moderate 1,162 No known interaction 1,668 (incl. Doxycyline)
Taking anything else?

Check Another of Your Medications Against Phellodendron

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

What to actually watch for

No Interaction Found — But Data Suggests Phellodendron and Doxycyline May Share a Side Effect

This is not an interaction. Neither one changes how your body handles the other, and nothing here says they react together. What our sources do show is that each has separately been linked to the effects below — so taking both can make those effects more likely to turn up, and harder to pin on one or the other if they do.

  • Headache Additional detail

    Phellodendron

    “Orally, a combination product containing extracts of phellodendron plus magnolia has been associated with single reports of shaking hands, perilabial numbness, fatigue, and headache in clinical research. However, it is unknown if this is related to phellodendron or some other factor.”

    Phellodendron · Natural Medicines adverse-effect record, reported in cluster headache.

    2 sources cited
    1. 14349. Garrison R, Chambliss WG. Effect of a proprietary Magnolia and Phellodendron extract on weight management: a pilot, double-blind, placebo-controlled clinical trial. Altern Ther Health Med 2006;12:50-4.
    2. 94901. Kalman DS, Feldman S, Feldman R, et al. Effect of a proprietary magnolia and phellodendron extract on stress levels in healthy women: a pilot, double-blind, placebo-controlled clinical trial. Nutr J 2008;7:11.

    Doxycyline

    Listed in the ADVERSE REACTIONS section of the FDA label for Doxycyline. Read the label on DailyMed ›

Reported for Phellodendron but not commonly for Doxycyline: erection problems, heartburn, numbness or tingling and tremor or shakiness.

Effects for Doxycyline come from the ADVERSE REACTIONS section of its FDA label; effects for Phellodendron come from the Natural Medicines adverse-effect record, quoted above. Wording is matched across sources by our own clinical vocabulary, so treat this as a prompt to pay attention, not a diagnosis.

Special populations

Phellodendron in Pregnancy & Breastfeeding

Lactation Likely Unsafe

When used orally. The berberine constituent of phellodendron 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

How to take them

Some Doxycyline Products Have a Food Rule — Phellodendron Should Not Break It

At least one FDA label for a product containing Doxycyline says to take it on an empty stomach. Most supplements — Phellodendron included — are taken with a meal, so the easy mistake is swallowing both together at breakfast. Where that rule applies, keep Doxycyline on its own and move Phellodendron to a meal later in the day.

This may not be true of your version. Food instructions belong to the product, not the ingredient: two Doxycyline products can carry different directions, and extended-release forms often differ from immediate-release ones. The label we read is quoted below — check the directions on your own box or bottle, or ask your pharmacist, for how to take the exact product you were given.

2 DOSAGE AND ADMINISTRATION Take one Doxycycline capsule (40 mg) once daily in the morning on an empty stomach, preferably at least one hour prior to or two hours after meals.

From the Dosage and Administration section of the FDA label we read for Doxycyline — where that label names a specific product, the instruction is that product's. Read the label on DailyMed ›

A food rule is not an interaction — it is about how much of the medicine you absorb. The directions that came with your own product, and your pharmacist, outrank anything on this page.

From our Q&A

Questions About Phellodendron or Doxycyline

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

This page covers Phellodendron only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Doxycyline page lists 149 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Asarabacca (major), Beer (major), Oleander (major), Siberian Cocklebur (major) and St. John's Wort (major).

By severity: 6 major · 132 moderate · 11 minor.

From our pharmacist’s overview on the Doxycyline page

“I read the supplement list for doxycycline (Doxychel) as one to approach with real care, starting with its major-rated entries. Heavy alcohol, including beer and wine, adds to the liver strain this antibiotic can cause, botanicals such as Siberian cocklebur can compound stress on the kidneys, and St.”

Reviewed by 2 · Jul 18, 2026

Open the Doxycyline interaction page

One more smart check

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

We hold 393 real supplement products containing Phellodendron, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Phellodendron. Even though Phellodendron itself has no known interaction with Doxycyline, 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 Phellodendron and Doxycyline 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 Phellodendron
Top 25%

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

29 days ago today
Medication Doxycyline
Top half

#1,364 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 Phellodendron reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified October 4, 2026. The Phellodendron and Doxycyline 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 Phellodendron

What is Phellodendron?

Phellodendron
  • Digestive complaints and diarrhea
  • Inflammation and joint discomfort
  • Stress and weight management (in combination products)
  • Skin conditions (topical, traditional)
  • Antimicrobial support

Phellodendron is a traditional Chinese medicine bark (Huang Bai) that contains berberine and other plant compounds with antimicrobial and anti-inflammatory activity in lab studies. Human evidence for most uses is limited, and it is often sold in combination with other herbs, making its individual effects hard to judge. Talk with your pharmacist or doctor before using it, and avoid it during pregnancy and breastfeeding.

Phellodendron amurense · Rutaceae · Bark (cortex) · Capsules, tablets, powders, tinctures, and dried bark used in teas or decoctions; often combined with other herbs

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

Phellodendron: dosing

There is no well-established, standardized dose of Phellodendron for any health condition. Products vary widely in strength and may contain other herbs, which makes general dosing advice difficult.If you choose to use it, follow the directions on the product label and do not exceed the recommended amount.

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

Read the full Phellodendron monograph & all interactions
Medication

About Doxycycline

What Is Doxycycline Used For?

Brand name: Doxychel

Doxycycline is an antibiotic. It treats infections caused by bacteria, and it does not work on viruses.

Several products carry a broad list of uses, including rickettsial infections, sexually transmitted infections, respiratory tract infections, eye infections, and anthrax after exposure. Some product labels also list malaria prevention, and use as an add-on treatment for acute intestinal amebiasis and severe acne. Doxycycline for Injection (Doxy 100, intravenous) is approved for infections caused by a listed set of microorganisms. Doxycycline capsules in the Oracea-type low-dose form are described in the evidence for inflammatory lesions of rosacea.

See full Doxycycline drug information
Keep checking

Other Drugs & Phellodendron

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

0Major
1,162Moderate
0Minor
1,667No known interaction
1,162 Moderate 1,667 No interaction
Moderate

1,162 interactions

Showing 60 of 1,162 moderate interactions — see all 1,162 on the Phellodendron page.

No interaction 1,667 drugs checked — show the list

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

Showing the 60 most looked-up of 1,667 medications checked with no known interaction — see the full Phellodendron list.

See the full Phellodendron interactions page
See every supplement checked against Doxycyline, ranked by severity
Evidence & sources

Phellodendron References

The 22 references that drive our Phellodendron 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. Chan E. Displacement of bilirubin from albumin by berberine. Biol Neonate 1993;63:201-8. PubMed
  2. Janbaz KH, Gilani AH. Studies on preventive and curative effects of berberine on chemical-induced hepatotoxicity in rodents. Fitoterapia 2000;71:25-33.. PubMed
  3. 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
  4. Garrison R, Chambliss WG. Effect of a proprietary Magnolia and Phellodendron extract on weight management: a pilot, double-blind, placebo-controlled clinical trial. Altern Ther Health Med 2006;12:50-4.
  5. 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
  6. 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
  7. 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
  8. 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
  9. 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.
  10. 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
  11. Sabir M and Bhide NK. Study of some pharmacological actions of berberine. Ind J Physiol & Pharmac 1971;15(3):111-132.
  12. Tripathi YB and Shukla SD. Berberis artistata inhibits PAF induced aggregation of rabbit platelets. Phytotherapy Research 1996;10:628-630.
  13. Yin, J., Xing, H., and Ye, J. Efficacy of berberine in patients with type 2 diabetes mellitus. Metabolism 2008;57(5):712-717. PubMed
  14. 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
  15. Guo, Y., Chen, Y., Tan, Z. R., Klaassen, C. D., and Zhou, H. H. Repeated administration of berberine inhibits cytochromes P450 in humans. Eur J Clin Pharmacol 2012;68(2):213-217. PubMed

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 Phellodendron and Doxycyline Together: Common Questions

Is it safe to take Phellodendron with Doxycyline?
We do not list a known interaction between Phellodendron and Doxycyline. 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.
Do Phellodendron and Doxycyline have any of the same side effects?
Yes — our sources link each of them separately to one of the same effects. That is not an interaction: neither changes how your body handles the other. It does mean that if one of those effects turns up, it can be harder to tell which one is behind it. They are listed on this page with the source behind each.
Should I take Phellodendron and Doxycyline at the same time of day?
At least one FDA label for a product containing Doxycyline says to take it on an empty stomach, and supplements are usually taken with a meal — so taking them together at breakfast is the easy mistake. Where that applies, keep Doxycyline on its own and move Phellodendron to a meal later in the day. Food instructions belong to the product rather than the ingredient, so check the directions on your own box. This is about absorption, not an interaction.
How was the Phellodendron and Doxycyline combination checked?
Interactions in our licensed database are recorded against drug classes. Doxycyline is filed under 8 classifications, and Phellodendron has documented interactions with 14 drug classes — none of Doxycyline'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 Phellodendron interact with any other medications?
Yes. Phellodendron has 1,162 documented drug interactions in our database — Doxycyline 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 Doxycyline interact with any supplements?
Yes. Doxycyline has documented interactions with 149 supplements in our database — Phellodendron is not one of them. The Doxycyline interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Phellodendron monograph Uses, safety profile, and every drug interaction in one place Doxycycline drug information The full plain-English guide to this medication Doxycyline supplement interactions Every supplement checked against Doxycyline, 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 References The 22 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Doxycyline and Phellodendron?

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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.