Drug & supplement interaction

Cocoa + Guaifenesin, Phenylephrine, Phenylpropanolamine

Guaifenesin, Phenylephrine, Phenylpropanolamine brand names: Dura Gest, Entex.

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

Guaifenesin, Phenylephrine, Phenylpropanolamine falls into 2 drug categories that Cocoa can interact with; the most serious is rated moderate. Theoretically, concomitant use might increase stimulant adverse effects.

Read the full interaction report
SeverityModerate
LikelihoodProbable
Interactions2
EvidenceC
What do Severity, Likelihood & Evidence mean?
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Interaction report

Cocoa and Guaifenesin, Phenylephrine, Phenylpropanolamine

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Cocoa interacts with whole categories of medication. Guaifenesin, Phenylephrine, Phenylpropanolamine falls into 2 of those categories, so it can interact with Cocoa in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

STIMULANT DRUGS

1 of 2

Why this applies to Guaifenesin, Phenylephrine, Phenylpropanolamine

Guaifenesin, Phenylephrine, Phenylpropanolamine falls under STIMULANT DRUGS — the group Cocoa interacts with.

Theoretically, concomitant use might increase stimulant adverse effects.
Cocoa contains caffeine. Concomitant use might increase the risk of stimulant adverse effects.
Severity Moderate Likelihood Probable Evidence C

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 simple version. This cold and cough combo includes phenylephrine and phenylpropanolamine, which are decongestants that work by tightening up blood vessels and can act like mild stimulants. Cocoa naturally contains a little caffeine (plus a related compound, theobromine), so pairing the two could pile one stimulant effect on top of another.

In practice that might mean a faster or pounding heartbeat, jitteriness, trouble sleeping, or a bump in blood pressure. To be fair, this concern is mostly theoretical and based on expert opinion, and a normal cup of hot cocoa or a bit of chocolate usually isn't a big deal. Concentrated cocoa supplements are where I'd be more cautious, especially if you have heart issues or high blood pressure. Check with your pharmacist or doctor before combining them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Institute of Medicine. Caffeine for the Sustainment of Mental Task Performance: Formulations for Military Operations. Washington, DC: National Academy Press, 2001. Available at: http://books.nap.edu/books/0309082587/html/index.html. DOI
Moderate

PHENYLPROPANOLAMINE

2 of 2

Guaifenesin, Phenylephrine, Phenylpropanolamine also falls under PHENYLPROPANOLAMINE.

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of caffeine.
Cocoa contains caffeine. Concomitant use of phenylpropanolamine and caffeine might cause an additive increase in blood pressure. Phenylpropanolamine also seems to increase caffeine serum levels.
Severity Moderate Likelihood Probable Evidence B

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

The piece of your combo product that matters here is the decongestant. Both phenylpropanolamine and phenylephrine work by tightening blood vessels, which can nudge your blood pressure up on their own. Cocoa naturally contains some caffeine, and the concern is twofold: the caffeine can add to that blood pressure bump, and the decongestant may slow how fast you clear caffeine, so it lingers and hits harder.

In real life this could mean feeling jittery, a racing or pounding heart, trouble sleeping, or a higher blood pressure reading, especially if you already have hypertension. A cup of cocoa is usually mild, but concentrated cocoa supplements are a bigger deal. Please check with your pharmacist or doctor before pairing them, rather than stopping anything on your own.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Brown NJ, Ryder D, Branch RA. A pharmacodynamic interaction between caffeine and phenylpropanolamine. Clin Pharmacol Ther 1991;50:363-71. PubMed
  2. Lake CR, Rosenberg DB, Gallant S, et al. Phenylpropanolamine increases plasma caffeine levels. Clin Pharmacol Ther 1990;47:675-85. 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 Guaifenesin, Phenylephrine, Phenylpropanolamine one above is among them. If you take anything else, check it against the full list below.

Moderate 634 Minor 26 No known interaction 2,170 (incl. Guaifenesin, Phenylephrine, Phenylpropanolamine)
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 Guaifenesin, Phenylephrine, Phenylpropanolamine

This page covers Cocoa only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Guaifenesin, Phenylephrine, Phenylpropanolamine page lists 62 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Ephedra (major), Peyote (major), Rauvolfia Vomitoria (major) and Sida Cordifolia (major).

By severity: 5 major · 44 moderate · 13 minor.

From our pharmacist’s overview on the Guaifenesin, Phenylephrine, Phenylpropanolamine page

“Entex (guaifenesin, phenylephrine, phenylpropanolamine) treats congestion with two decongestants that behave like mild stimulants, squeezing blood vessels and pushing blood pressure up. That built-in stimulant effect is why its list of 62 supplement interactions deserves genuine care, and why five entries rate major.”

Reviewed by 2 · Jul 18, 2026

Open the Guaifenesin, Phenylephrine, Phenylpropanolamine 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 Guaifenesin, Phenylephrine, Phenylpropanolamine 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 Guaifenesin, Phenylephrine, Phenylpropanolamine 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%

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

29 days ago today
Medication Guaifenesin, Phenylephrine, Phenylpropanolamine
Steady interest

#1,760 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
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 Guaifenesin, Phenylephrine, Phenylpropanolamine, 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 Guaifenesin, Phenylephrine, Phenylpropanolamine supplement interactions › Every supplement checked against Guaifenesin, Phenylephrine, Phenylpropanolamine, 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 Ask a pharmacist › Free, personal answer from our licensed team
Pharmacist Counseling Corner

Taking Cocoa and Guaifenesin, Phenylephrine, Phenylpropanolamine Together: Common Questions

Can you take Cocoa with Guaifenesin, Phenylephrine, Phenylpropanolamine?
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.
Why are there 2 interactions listed for Cocoa and Guaifenesin, Phenylephrine, Phenylpropanolamine?
Guaifenesin, Phenylephrine, Phenylpropanolamine belongs to more than one drug category, and Cocoa interacts with each of those categories a little differently. We list every one so nothing is missed — your overall risk is driven by the most serious of them.
How serious is the Cocoa and Guaifenesin, Phenylephrine, Phenylpropanolamine 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 Guaifenesin, Phenylephrine, Phenylpropanolamine 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.