Drug & supplement interaction

Cocoa + Metaproterenol

Metaproterenol brand names: Metaproterenol, Metaprel.

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

Cocoa has a moderate interaction with Metaproterenol. Theoretically, large amounts of cocoa might increase the cardiac inotropic effects of beta-agonists.

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

Cocoa and Metaproterenol

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

Moderate

BETA-ADRENERGIC AGONISTS

Why this applies to Metaproterenol

Metaproterenol falls under BETA-ADRENERGIC AGONISTS — the group Cocoa interacts with.

Theoretically, large amounts of cocoa might increase the cardiac inotropic effects of beta-agonists.
Cocoa contains caffeine. Theoretically, large amounts of caffeine might increase cardiac inotropic effects of beta-agonists. A case of atrial fibrillation associated with consumption of large quantities of chocolate in a patient with chronic albuterol inhalation abuse has also been reported.
Severity Moderate Likelihood Probable Evidence D

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..

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

Here's the gist: metaproterenol is a beta-agonist that opens up your airways, but it can also speed up and strengthen your heartbeat as a side effect. Cocoa contains caffeine, which is a mild stimulant of its own. The concern is that the two together could nudge your heart a little harder, possibly leading to a faster heart rate, palpitations, or that jittery, racing feeling. There's even a rare report of an irregular heartbeat (atrial fibrillation) in someone overusing an inhaler along with lots of chocolate.

That said, this is theoretical and based on pharmacology, not strong human studies. A normal cup of hot cocoa or a chocolate treat is very unlikely to cause trouble. Concentrated cocoa supplements or big amounts are where I'd be more cautious. If you notice your heart pounding or feel shaky, check in with your pharmacist or doctor.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. McEvoy GK, ed. AHFS Drug Information. Bethesda, MD: American Society of Health-System Pharmacists, 1998.
  2. Patane, S., Marte, F., La Rosa, F. C., and Rocca, R. L. Atrial fibrillation associated with chocolate intake abuse and chronic salbutamol inhalation abuse. Int J Cardiol. 1-24-2009; 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

Cocoa Also Interacts With Other Medications

Cocoa has 634 moderate, 26 minor known drug interactions in our database — the Metaproterenol one above is one of them. If you take anything else, check it against the full list below.

Moderate 634 Minor 26 No known interaction 2,170 (incl. Metaproterenol)
Taking anything else?

Check Another of Your Medications Against Cocoa

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

Everything else you take

See Every Supplement That Interacts With Metaproterenol

This page covers Cocoa only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Metaproterenol page lists 32 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Black Tea (moderate), Caffeine (moderate), Coffee (moderate) and Coffee Charcoal (moderate).

By severity: 1 major · 22 moderate · 9 minor.

From our pharmacist’s overview on the Metaproterenol page

“Metaproterenol is an older bronchodilator for asthma and COPD, and because the receptors it stimulates to open the airways also quicken the heart, its 32 interacting supplements call for real vigilance. The lone major entry is activated charcoal, which can bind the drug and cut how much reaches your bloodstream.”

Reviewed by 2 · Jul 18, 2026

Open the Metaproterenol interaction page

One more smart check

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

We hold 844 real supplement products containing Cocoa, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cocoa. Your product may carry other ingredients that interact with Metaproterenol too, on top of Cocoa — 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 Cocoa and Metaproterenol 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 Cocoa
Top 25%

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

29 days ago today
Medication Metaproterenol
Steady interest

#2,758 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 Cocoa

What is Cocoa?

Cocoa
  • Heart and blood vessel health
  • High blood pressure
  • High cholesterol
  • Mental focus and mood
  • Skin moisturizing (cocoa butter)

Cocoa is rich in plant compounds called flavanols that may modestly support blood vessel function and blood pressure, but most chocolate products are high in sugar, fat, and calories, which can offset any benefit. Enjoy cocoa as part of a balanced diet, and talk to your pharmacist before using concentrated cocoa supplements, especially if you have heart or blood pressure conditions.

Read the full Cocoa monograph & all interactions
Medication

About Metaproterenol

What Is Metaproterenol Used For?

Brand names: Metaproterenol, Metaprel

  • Metaproterenol is used to prevent and treat wheezing, shortness of breath, coughing, and chest tightness caused by asthma, chronic bronchitis, emphysema, and other lung diseases. It relaxes and opens air passages in the lungs, making it easier to breathe.

See full Metaproterenol drug information
Keep checking

Other Drugs & Cocoa

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

0Major
634Moderate
26Minor
2,169No known interaction
634 Moderate 26 Minor 2,169 No interaction
Moderate

634 interactions

Showing 60 of 634 moderate interactions — see all 634 on the Cocoa page.

Minor

26 interactions

No interaction 2,169 drugs checked — show the list

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

Showing the 60 most looked-up of 2,169 medications checked with no known interaction — see the full Cocoa list.

See the full Cocoa interactions page
See every supplement checked against Metaproterenol, 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
Cocoa monograph › Uses, safety, and every drug interaction in one place Metaproterenol supplement interactions › Every supplement checked against Metaproterenol, ranked by severity Metaproterenol 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 Cocoa and Metaproterenol Together: Common Questions

Can you take Cocoa with Metaproterenol?
There is a moderate interaction, so it may be acceptable with monitoring or timing changes — but check with your pharmacist first. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Cocoa and Metaproterenol interaction?
We rate it Moderate. This combination may require monitoring, a dose adjustment, or separating the times you take each one. Consult your pharmacist before using them together.

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

Still Have a Question About Metaproterenol and Cocoa?

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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.