Drug & supplement interaction

Hordenine + Alvimopan

Alvimopan brand name: Entereg.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 20, 2026
The bottom line No known interaction

We found no known interaction between Hordenine and Alvimopan 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

Hordenine and Alvimopan

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 Alvimopan and Hordenine 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.

Hordenine safety at a glance

Hordenine overall Use caution Human safety data is very limited, and it acts as a stimulant.
Pregnancy Avoid No safety data; avoid use during pregnancy.
Breastfeeding Avoid No safety data; avoid while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Alvimopan and Hordenine? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Alvimopan

Interactions in our licensed database are recorded against drug classes, not just single drug names. Alvimopan is filed under 2 classifications — p-glycoprotein substrates, oral drugs. Hordenine has documented interactions with 3 drug classes — the most serious being monoamine oxidase inhibitors (maois) (moderate), stimulant drugs (moderate) and cytochrome p450 2d6 (cyp2d6) substrates (minor) — and none of Alvimopan’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

Hordenine Does Interact With Other Medications

Hordenine has 180 moderate, 149 minor known drug interactions in our database — Alvimopan isn’t one of them. If you take anything else, check it against the full list below.

Moderate 180 Minor 149 No known interaction 2,501 (incl. Alvimopan)
Taking anything else?

Check Another of Your Medications Against Hordenine

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

What to actually watch for

What Hordenine Itself Has Been Linked To

This is not an interaction — nothing below involves Alvimopan. It is the side-effect record for Hordenine on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Hordenine, this list is the first place to look. One entry is worth acting on rather than waiting out — marked below.

  • Raised blood pressure Worth acting on Additional detail

    “No clinical studies have evaluated the safety of hordenine in humans. However, hordenine is structurally similar to the stimulants N-methyltyramine and synephrine, which are found in bitter orange. Theoretically, hordenine may cause stimulant-related side effects similar to these compounds, including tachycardia and hypertension.”

    Hordenine · Natural Medicines adverse-effect record, reported in hypertension.

    1 source cited
    1. 29888. Nelson BC, Putzbach K, Sharpless KE, Sander LC. Mass spectrometric determination of the predominant adrenergic protoalkaloids in bitter orange (Citrus aurantium). J Agric Food Chem 2007;55(24):9769-75. PubMed

    “Hordenine is structurally similar to the stimulants N-methyltyramine and synephrine, which are found in bitter orange. Theoretically, hordenine may cause stimulant-related side effects similar to these compounds, including tachycardia and hypertension. However, this has not been assessed or reported in humans.”

    Hordenine · Natural Medicines adverse-effect record, reported in hypertension.

    1 source cited
    1. 29888. Nelson BC, Putzbach K, Sharpless KE, Sander LC. Mass spectrometric determination of the predominant adrenergic protoalkaloids in bitter orange (Citrus aurantium). J Agric Food Chem 2007;55(24):9769-75. PubMed
  • A fast or pounding heartbeat Additional detail

    Recorded for Hordenine in the same Natural Medicines adverse-effect record shown under Raised blood pressure above.

Everything above comes from the Natural Medicines adverse-effect record for Hordenine — expand a row for the licensed statement it rests on. We read the ADVERSE REACTIONS section of Alvimopan’s FDA label too, and the two lists don’t meaningfully overlap — which is why no Alvimopan column appears here.

Everything else you take

See Every Supplement That Interacts With Alvimopan

This page covers Hordenine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Alvimopan page lists 54 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), St. John's Wort (major), Bitter Melon (moderate), Black Pepper (moderate) and Bulbine Natalensis (moderate).

By severity: 2 major · 35 moderate · 17 minor.

From our pharmacist’s overview on the Alvimopan page

“Alvimopan (Entereg) is given for a few days after bowel surgery to help the gut start moving again, and its supplement list warrants genuine care, with two entries rated major. St.”

Reviewed by 2 · Jul 18, 2026

Open the Alvimopan interaction page

One more smart check

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

We hold 339 real supplement products containing Hordenine, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Hordenine. Even though Hordenine itself has no known interaction with Alvimopan, 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 Hordenine and Alvimopan 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 Hordenine
Top 25%

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

29 days ago today
Medication Alvimopan
Top 10%

#184 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 Hordenine reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Hordenine and Alvimopan records this page draws on were last updated July 10, 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 Hordenine

What is Hordenine?

Hordenine
  • Energy and stimulation
  • Athletic and workout performance
  • Weight loss/fat burning
  • Focus and mood
  • Appetite control

Hordenine is a natural alkaloid found in barley and some cacti that is marketed as a stimulant for energy, focus, and fat loss, but solid human evidence for these benefits is lacking. Its safety in people has not been well studied, so caution is warranted, and it should be avoided in pregnancy, breastfeeding, and by people with heart conditions.

Alkaloid isolated from plants such as barley sprouts and certain cacti · Capsules, tablets, powders (often in pre-workout and 'fat burner' blends)

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

Hordenine: dosing

There is no established, well-studied dose for hordenine. The amounts found in supplements vary widely, and they have not been tested for safety or effectiveness in proper human trials.If you choose to use a product containing hordenine, follow the label instructions and do not exceed them. Be aware that it is often mixed with caffeine and other stimulants, so the total stimulant load may be higher than it appears.

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

Read the full Hordenine monograph & all interactions
Medication

About Alvimopan

What Is Alvimopan Used For?

Brand name: Entereg

Alvimopan capsules are used in hospitals to help the digestive tract recover more quickly after surgery that involves removing part of the bowel (partial bowel resection with primary anastomosis — meaning the remaining ends are reconnected). After this type of surgery, the bowel often temporarily stops working, a condition called postoperative ileus.

This medication is only given during a short hospital stay and is not for long-term or home use.

Most-Reported Side Effects for Alvimopan

From FAERS, the FDA’s public side-effect reporting system (43 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Hospitalisation 19 reports
Acute kidney injury 5 reports
Acute myocardial infarction 4 reports
Ileus 3 reports
Pruritus 3 reports
See full Alvimopan drug information
Keep checking

Other Drugs & Hordenine

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

0Major
180Moderate
149Minor
2,500No known interaction
180 Moderate 149 Minor 2,500 No interaction
Moderate

180 interactions

Showing 60 of 180 moderate interactions — see all 180 on the Hordenine page.

Minor

149 interactions

Showing 60 of 149 minor interactions — see all 149 on the Hordenine page.

No interaction 2,500 drugs checked — show the list

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

Showing the 60 most looked-up of 2,500 medications checked with no known interaction — see the full Hordenine list.

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

Hordenine References

The 3 references that drive our Hordenine 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. Barwell CJ, Basma AN, Lafi MA, Leake LD. Deamination of hordenine by monoamine oxidase and its action on vasa deferentia of the rat. J Pharm Pharmacol 1989;41(6):421-3. PubMed
  2. Nelson BC, Putzbach K, Sharpless KE, Sander LC. Mass spectrometric determination of the predominant adrenergic protoalkaloids in bitter orange (Citrus aurantium). J Agric Food Chem 2007;55(24):9769-75. PubMed
  3. Liu Y, Santillo MF. Cytochrome P450 2D6 and 3A4 enzyme inhibition by amine stimulants in dietary supplements. Drug Test Anal. 2016;8(3-4):307-10. 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 Hordenine and Alvimopan Together: Common Questions

Is it safe to take Hordenine with Alvimopan?
We do not list a known interaction between Hordenine and Alvimopan. 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 Hordenine and Alvimopan combination checked?
Interactions in our licensed database are recorded against drug classes. Alvimopan is filed under 2 classifications, and Hordenine has documented interactions with 3 drug classes — none of Alvimopan'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 Hordenine interact with any other medications?
Yes. Hordenine has 329 documented drug interactions in our database — Alvimopan 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 Alvimopan interact with any supplements?
Yes. Alvimopan has documented interactions with 54 supplements in our database — Hordenine is not one of them. The Alvimopan 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

Hordenine monograph Uses, safety profile, and every drug interaction in one place Alvimopan drug information The full plain-English guide to this medication Alvimopan supplement interactions Every supplement checked against Alvimopan, 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 3 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Alvimopan and Hordenine?

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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.