Drug & supplement interaction

Cola Nut + Guaifenesin, Phenylpropanolamine

Guaifenesin, Phenylpropanolamine brand names: Entex LA, Miraphen PE, Dura-Vent, Guaifed, Guaifed-PD, and others.

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

Guaifenesin, Phenylpropanolamine falls into 2 drug categories that Cola Nut 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

Cola Nut and Guaifenesin, Phenylpropanolamine

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

Why Are There 2 Interactions?

Cola Nut interacts with whole categories of medication. Guaifenesin, Phenylpropanolamine falls into 2 of those categories, so it can interact with Cola Nut 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, Phenylpropanolamine

Guaifenesin, Phenylpropanolamine falls under STIMULANT DRUGS — the group Cola Nut interacts with.

Theoretically, concomitant use might increase stimulant adverse effects.
Cola nut contains caffeine. Due to the central nervous system (CNS) stimulant effects of caffeine, concomitant use with stimulant drugs can increase the risk of 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. These combo products pair guaifenesin, which just thins out mucus and is pretty quiet on this front, with phenylpropanolamine, a decongestant that already nudges your nervous system and can speed up your heart and raise blood pressure. Cola nut brings caffeine to the table, another stimulant. Stack two stimulant-type effects together and you may feel them more strongly.

What that can look like in real life: a racing or pounding heart, jitteriness, trouble sleeping, headache, or a bump in blood pressure. This is mostly an expert-opinion, theoretical concern, not a dramatic clash, and a little caffeine from food likely won't matter much. Still, if you have heart issues or high blood pressure, check with your pharmacist or doctor before combining them regularly.

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, Phenylpropanolamine also falls under PHENYLPROPANOLAMINE.

Theoretically, phenylpropanolamine might increase the risk of hypertension, as well as the levels and adverse effects of the caffeine in cola nut.
Cola nut 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

This combination product pairs guaifenesin (a mucus thinner that doesn't really interact here) with phenylpropanolamine, a decongestant-type stimulant that can nudge your blood pressure up. The piece to watch is the phenylpropanolamine. Cola nut is basically a caffeine source, and stacking caffeine on top of phenylpropanolamine can add up to a bigger bump in blood pressure than either one alone.

There's also a two-way push: phenylpropanolamine appears to raise caffeine levels in your blood, so you may feel more jittery, restless, fast-hearted, or have trouble sleeping. This is a fairly likely interaction, though much of the blood pressure concern is theoretical. If you have high blood pressure or a heart condition, please run this by your pharmacist or doctor before combining them.

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

Cola Nut Also Interacts With Other Medications

Cola Nut has 546 moderate, 108 minor known drug interactions in our database — the Guaifenesin, Phenylpropanolamine one above is among them. If you take anything else, check it against the full list below.

Moderate 546 Minor 108 No known interaction 2,176 (incl. Guaifenesin, Phenylpropanolamine)
Taking anything else?

Check Another of Your Medications Against Cola Nut

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

Everything else you take

See Every Supplement That Interacts With Guaifenesin, Phenylpropanolamine

This page covers Cola Nut only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Guaifenesin, 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, Phenylpropanolamine page

“Ephedra is the entry I'd want anyone taking guaifenesin with phenylpropanolamine (Entex LA, Guaifed, Dura-Vent) to understand first. Phenylpropanolamine is a stimulant decongestant that can raise blood pressure on its own, and ephedra, along with three other stimulant herbs rated major, can stack on that effect and strain the heart.”

Reviewed by 2 · Jul 18, 2026

Open the Guaifenesin, Phenylpropanolamine interaction page

One more smart check

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

We hold 2 real supplement products containing Cola Nut, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cola Nut. Your product may carry other ingredients that interact with Guaifenesin, Phenylpropanolamine too, on top of Cola Nut — 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 Cola Nut and Guaifenesin, 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 Cola Nut
Steady interest

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

29 days ago today
Medication Guaifenesin, Phenylpropanolamine
Steady interest

#1,607 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 Cola Nut

What is Cola Nut?

Cola Nut
  • Energy and alertness
  • Mental focus
  • Physical performance
  • Weight loss support
  • Traditional digestive aid

Cola nut is a caffeine-containing seed from West Africa used mainly as a natural stimulant for energy and alertness. Most of its effects come from caffeine, and strong human evidence for specific health benefits is limited. Because of its caffeine content, people sensitive to stimulants and those who are pregnant or have heart conditions should be cautious.

Read the full Cola Nut monograph & all interactions
Keep checking

Other Drugs & Cola Nut

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

0Major
546Moderate
108Minor
2,175No known interaction
546 Moderate 108 Minor 2,175 No interaction
Moderate

546 interactions

Showing 60 of 546 moderate interactions — see all 546 on the Cola Nut page.

Minor

108 interactions

Showing 60 of 108 minor interactions — see all 108 on the Cola Nut page.

No interaction 2,175 drugs checked — show the list

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

Showing the 60 most looked-up of 2,175 medications checked with no known interaction — see the full Cola Nut list.

See the full Cola Nut interactions page
See every supplement checked against Guaifenesin, 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
Cola Nut monograph › Uses, safety, and every drug interaction in one place Guaifenesin, Phenylpropanolamine supplement interactions › Every supplement checked against Guaifenesin, 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 Cola Nut and Guaifenesin, Phenylpropanolamine Together: Common Questions

Can you take Cola Nut with Guaifenesin, 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 Cola Nut and Guaifenesin, Phenylpropanolamine?
Guaifenesin, Phenylpropanolamine belongs to more than one drug category, and Cola Nut 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 Cola Nut and Guaifenesin, 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, Phenylpropanolamine and Cola Nut?

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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.