Drug & supplement interaction

Hordenine + Formoterol

Formoterol brand names: Foradil Aerolizer, Atimos Modulite, Oxis Turbohaler, Perforomist, Foradil Certihaler.

Minor Interaction
Medically reviewed by · Updated September 2026
The bottom line Minor

Hordenine has a minor interaction with Formoterol. Hordenine weakly inhibits cytochrome P450 2D6 (CYP2D6) enzymes in vitro.

Read the full interaction report
SeverityMinor
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Hordenine and Formoterol

Here is the interaction we found between these two, with the evidence behind it.

Minor

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES

Why this applies to Formoterol

Formoterol falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES — the group Hordenine interacts with.

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.
Severity Minor Likelihood Possible Evidence D

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.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the situation with your Formoterol inhaler and hordenine. Lab testing suggests hordenine can mildly block an enzyme called CYP2D6, which is one route your body uses to clear formoterol. If that pathway slows a little, slightly more formoterol could hang around. In theory that might nudge up the usual beta-agonist side effects, things like a racing or pounding heart, shaky hands, jitteriness, or a headache.

I want to be honest about how weak this is. It comes only from test-tube work, the interaction is rated minor, and hordenine itself isn't well studied in people. On top of that, hordenine is a mild stimulant, so it could add to that jittery feeling on its own. If you notice your heart racing, check with your pharmacist or doctor before changing anything.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. 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

What These Ratings Mean

Every interaction above is graded three ways — here’s the key to each label.

Severity how clinically significant the interaction is
Major

Clinically significant. Avoid the combination, or use only under close professional supervision.

Moderate

Usually worth avoiding or managing — may need monitoring, a dose change, or timing apart.

Minor

Generally not serious. Be aware of it and mention it to your pharmacist.

Likelihood how strong the evidence is that the interaction actually happens in people
  • LikelyWell-controlled human studies have demonstrated the likely existence of this interaction.
  • ProbableInteraction 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.
  • PossibleInteraction 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.
  • UnlikelyInteraction has been demonstrated in animal or in lab research but has been shown not to occur in humans.
Evidence the quality of the studies behind the rating (graded A–D)
  • AHigh-quality meta-analysis (quantitative systematic review).
  • BCase-control study.
  • CConsensus.
  • DAnecdotal evidence.

These ratings are for information only. Never start, stop, or otherwise change your therapy before speaking with your provider.

Keep it in perspective

Hordenine Also Interacts With Other Medications

Hordenine has 180 moderate, 148 minor known drug interactions in our database — the Formoterol one above is one of them. If you take anything else, check it against the full list below.

Moderate 180 Minor 148 No known interaction 2,502 (incl. Formoterol)
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.

Everything else you take

See Every Supplement That Interacts With Formoterol

This page covers Hordenine only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Formoterol page lists 103 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,3-dmaa (moderate), Acacia Rigidula (moderate), Active Hexose Correlated Compound (ahcc) (moderate), Adrafinil (moderate) and African Wild Potato (moderate).

By severity: 84 moderate · 19 minor.

From our pharmacist’s overview on the Formoterol page

“Formoterol (Foradil, Perforomist) is the long-acting half of many asthma and COPD inhalers, keeping airways open for hours, and its supplement list is calmer than its length suggests. None of the 103 ingredients on file is rated major.”

Reviewed by 2 · Jul 18, 2026

Open the Formoterol 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. Your product may carry other ingredients that interact with Formoterol too, on top of Hordenine — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Hordenine and Formoterol 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%

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

29 days ago today
Medication Formoterol
Steady interest

#1,525 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.

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.

Read the full Hordenine monograph & all interactions
Medication

About Formoterol Oral Inhalation

What Is Formoterol Oral Inhalation Used For?

Brand names: Foradil Aerolizer, Atimos Modulite, Oxis Turbohaler, Perforomist, Foradil Certihaler

Formoterol fumarate inhalation solution is used for the long-term maintenance treatment of airway narrowing (bronchoconstriction) in adults with COPD, including chronic bronchitis and emphysema. It is taken twice daily — morning and evening — as a regular, ongoing treatment.

Important limits: This medication is not for relieving sudden COPD flare-ups or breathlessness in the moment, and it is not approved to treat asthma. A separate short-acting inhaler should always be on hand for sudden symptoms.

See full Formoterol Oral Inhalation 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
148Minor
2,501No known interaction
180 Moderate 148 Minor 2,501 No interaction
Moderate

180 interactions

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

Minor

148 interactions

Showing 60 of 148 minor interactions — see all 148 on the Hordenine page.

No interaction 2,501 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 2,501 medications checked with no known interaction — see the full Hordenine list.

See the full Hordenine interactions page
See every supplement checked against Formoterol, ranked by severity
Sources

Sources & How We Checked

Interaction details are evidence-graded and sourced from the Natural Medicines database. The medication overview comes from MedlinePlus.

Content is written and reviewed by licensed HelloPharmacist pharmacists. See our data sources and editorial standards for how this information is built and checked.

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

Keep exploring
Hordenine monograph › Uses, safety, and every drug interaction in one place Formoterol supplement interactions › Every supplement checked against Formoterol, ranked by severity Formoterol Oral Inhalation drug information › The full plain-English guide to this medication Supplement interaction checker › Check any supplement or product against your medications Browse medications A–Z › Every drug we've checked against herbs & supplements Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Hordenine and Formoterol Together: Common Questions

Can you take Hordenine with Formoterol?
There is only a minor interaction, which is usually not serious. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Hordenine and Formoterol interaction?
We rate it Minor. This interaction is generally not clinically significant, but it remains worth noting and discussing with your pharmacist.

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

Still Have a Question About Formoterol 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.