Herb & supplement monograph

Hordenine Drug Interactions, Uses, Safety & More

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS ·Updated July 2026

What is this page for?

First and foremost: how Hordenine interacts with medications. The heart of this page is the interaction list — every drug Hordenine is known to interact with, and how serious each one is.

But these pages have grown well beyond that into a full monograph — what Hordenine 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

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Interaction report

Drugs that interact with Hordenine

329 medications have a known interaction with Hordenine, graded by severity. Select any drug for the full evidence-based detail.

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Tell us the medications you take and we’ll check each one against Hordenine using our pharmacist-reviewed interaction data.

AI summaries are generated from our Hordenine interaction data for education only — always confirm with your pharmacist. How we use AI

2,830 drugs

Read The List Like a Pharmacist

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 Hordenine combination — clinical detail, likelihood, evidence level, and citations.
Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

The big picture

The kinds of drugs Hordenine affects

Every type of medication (drug category) Hordenine is known to interact with. Open any category for the detail — or search your exact drug in the checker above.

All 3 drug categories Hordenine interacts with

Monoamine Oxidase Inhibitors (maois)Stimulant DrugsCytochrome P450 2d6 (cyp2d6) Substrates

Monoamine Oxidase Inhibitors (Maois)

Hordenine is structurally similar to tyramine In vitro research shows that hordenine is a selective substrate for monoamine oxidase-B in the liver. Theoretically, concomitant use of hordenine with MAOIs might increase blood pressure, potentially leading to a hypertensive crisis.
Some MAOIs include isocarboxazid (Marplan), phenelzine (Nardil), selegiline (Eldepryl, Emsam, Zelapar), and tranylcypromine (Parnate).

Likelihood Possible Evidence D

Stimulant Drugs

Hordenine is structurally similar to N-methyltyramine and synephrine, constituents in bitter orange known to have stimulant properties. Theoretically, taking hordenine with drugs with stimulant properties might increase the risk of hypertension and other adverse cardiovascular effects.
Some of these drugs include amphetamine, caffeine, methylphenidate, pseudoephedrine, and many others.

Likelihood Possible Evidence D

Cytochrome P450 2D6 (Cyp2D6) Substrates

Hordenine weakly inhibits cytochrome P450 2D6 (CYP2D6) enzymes in vitro. Theoretically, hordenine might increase the levels of CYP2D6 substrates.
Some of drugs that are CYP2D6 substrates include amitriptyline (Elavil), clozapine (Clozaril), codeine, desipramine (Norpramin), donepezil (Aricept), fentanyl (Duragesic), flecainide (Tambocor), fluoxetine (Prozac), meperidine (Demerol), methadone (Dolophine), metoprolol (Lopressor, Toprol XL), olanzapine (Zyprexa), ondansetron (Zofran), tramadol (Ultram), trazodone (Desyrel), and others.

Likelihood Possible Evidence D

Monograph

Hordenine: Uses, Safety & Side Effects

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Reviewed July 2026 ·

The bottom line

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.

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

People commonly use it for

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

Popular and traditional uses — not proof it works. See “Uses & effectiveness” below for the evidence.

Safety at a glance

OverallUse caution

Human safety data is very limited, and it acts as a stimulant.

PregnancyBest avoided

No safety data; avoid use during pregnancy.

BreastfeedingBest avoided

No safety data; avoid while breastfeeding.

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

Jump to a section

Overview

Hordenine is a naturally occurring alkaloid first isolated from barley (the Hordeum genus, which gives it its name). It is also found in certain cacti and in sprouted grains. Chemically, it belongs to a family of compounds related to other stimulants the body makes, such as adrenaline.

Today, hordenine is mostly sold as a dietary supplement. You will often find it added to pre-workout drinks, energy products, and so-called 'fat burner' blends, where it is promoted for boosting energy, sharpening focus, and supporting weight loss. It is rarely sold as a single ingredient.

Uses & effectiveness

People take hordenine hoping it will give them more energy, better workout performance, sharper focus, or help with fat loss. These are popular marketing claims, not proven effects.

The honest summary is that good-quality human evidence is lacking. Most of what is known comes from older laboratory and animal studies, which suggest hordenine can act as a mild stimulant and affect the release of certain body chemicals. Whether these effects translate into real benefits for energy, exercise, or weight loss in people has not been reliably shown. At this time, there is not enough evidence to say hordenine works for any of its advertised uses.

How it works

Hordenine is structurally similar to compounds the body uses for its 'fight-or-flight' response. In laboratory studies, it appears to act as a mild stimulant, and it may influence the release or activity of norepinephrine (a natural chemical messenger involved in alertness and metabolism).

Some research suggests it may affect monoamine oxidase, an enzyme that breaks down certain brain and body chemicals. Supplement marketers use this to explain claims about energy and focus. It is important to understand that these mechanisms come mainly from test-tube and animal research, and they do not prove that hordenine produces meaningful or safe effects in humans.

Safety & precautions

The safety of hordenine in people has not been well studied. Because it can act as a stimulant, people with high blood pressure, heart disease, irregular heartbeat, anxiety, or thyroid problems should be especially careful and talk to a healthcare provider before using it.

Hordenine is often combined with other stimulants like caffeine in workout and weight-loss products, which can add to stimulant-related effects. Pregnant and breastfeeding people should avoid it because there is no safety information for these situations. Children, older adults, and anyone with a chronic health condition should also avoid it unless cleared by a doctor or pharmacist.

Also note that hordenine and similar stimulant ingredients can sometimes show up on drug or doping tests, which is a concern for competitive athletes.

Side effects

Because hordenine has not been studied carefully in humans, its full side-effect profile is unknown. Based on its stimulant-like nature, possible effects could include a faster heartbeat, raised blood pressure, jitteriness, restlessness, headache, or trouble sleeping.

More serious stimulant-related reactions, such as heart rhythm problems or a dangerous rise in blood pressure, are a theoretical concern, especially at higher doses or when combined with other stimulants. Stop using it and seek medical care if you notice chest pain, a pounding or irregular heartbeat, severe headache, or fainting.

Hordenine: Reported Adverse Effects

Documented safety reports on Hordenine from the evidence-graded Natural Medicines (TRC Healthcare) database, shown word-for-word from the licensed record.

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.

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.

Reports by condition

Hypertension Cardiovascular

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.

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.

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.

Adverse-effects data: Natural Medicines, Therapeutic Research Center

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. It is always best to check with a pharmacist or doctor first, especially if you take other medications or have any health conditions.

References & further reading

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.

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
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
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

Keep reading

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.

Brand directory

Brands that make products with Hordenine

132 brands in our database make a supplement containing Hordenine.

1 Up Nutrition 32 products 1st Phorm 75 products 8WeeksOut 12 products ABL Pharma 1 product Absorb Health 98 products Advanced Genetics 1 product AI Sports Nutrition 20 products ALLMAX 210 products ALLMAX NUTRITION 24 products Amazing Muscle 36 products American Metabolix 7 products American Muscle Sports Nutrition 3 products Anabolic Warfare 65 products Anarchy Labs 2 products ANS Performance 12 products Applied Nutriceuticals 30 products AS Aesthetics Sports 1 product ATS Labs 19 products Avanse Nutraceuticals 2 products Beast 12 products Betancourt Nutrition 28 products Biogear Begin Series 1 product BioSource Elite 1 product Black Label 1 product

Product directory

Supplement products with Hordenine

342 products in our database contain Hordenine. Open any to see its full ingredient list and every drug interaction we check.

Pharmacist Counseling Corner

Hordenine: Common Questions

Does Hordenine interact with prescription medications?

Yes. We list 329 medications with a known interaction with Hordenine. Use the checker above to see how Hordenine interacts with a specific drug.

How are Hordenine interactions rated?

Each interaction is graded major, moderate, or minor based on how clinically significant it is and the strength of the evidence behind it. Major interactions are the most serious and are best avoided, or used only under close professional supervision.

Is it safe to take Hordenine with my medications?

It depends on the specific medication. Some combinations are fine, while others call for monitoring, timing changes, or should be avoided. Check your exact drug above and confirm with your pharmacist or doctor before starting, stopping, or changing anything.

Where does this Hordenine interaction information come from?

Our interaction data is built on the Natural Medicines database — an evidence-graded reference for vitamins, herbs, and supplements — and is reviewed by licensed HelloPharmacist pharmacists, who may add clinical context.

What is Hordenine used for?

It is mainly marketed as a stimulant for energy, focus, workout performance, and fat loss, but there is little reliable human evidence that it works for any of these.

Is Hordenine safe to take?

Its safety in people has not been well studied. Because it acts like a stimulant, it may not be safe for people with heart problems, high blood pressure, or anxiety, so check with a healthcare provider first.

Can I take Hordenine while pregnant or breastfeeding?

No. There is no safety information for these situations, so it is best to avoid Hordenine during pregnancy and breastfeeding.

Could Hordenine cause a problem on a drug test?

Possibly. Hordenine and similar stimulant ingredients can sometimes interfere with drug or anti-doping tests, which is a concern for competitive athletes.

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

Keep exploring

Products that contain Hordenine

A rotating sample of real supplements in our database that list Hordenine — open any to see its full ingredients and every drug interaction we check.

See all 342 products with Hordenine →

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Hordenine Drug Interactions, Uses, Safety & More

Your Choice:

Drugs that interact with Hordenine

Don’t want to scroll the list? Just ask.

What Severity, Likelihood & Evidence Mean

Severity — How Serious It Can Be

Likelihood — How Well It’s Documented

Where This Data Comes From

The kinds of drugs Hordenine affects

Hordenine: Uses, Safety & Side Effects

Overview

Uses & effectiveness

How it works

Safety & precautions

Side effects

Hordenine: Reported Adverse Effects

Dosing

References & further reading

Brands that make products with Hordenine

Supplement products with Hordenine

Hordenine: Common Questions

Related supplements & herbs

Products that contain Hordenine

Have a question about Hordenine?