Medication interaction hub

What Supplements Interact with Guaifenesin, Phenylephrine?

Guaifenesin, Phenylephrine brand names: Amidal, Endal, Numonyl Sr, Liquibid-D, Deconsal Sprinkle, and others. Every interaction below applies to the brands too.

62 Interactions 5 Major 44 Moderate 13 Minor
Curated & coded by · Clinical Pharmacist · Updated September 15, 2026

Drug–supplement interaction data sourced from Natural Medicines Pro, the licensed clinical database from TRC Healthcare / Therapeutic Research, with additional analysis by the HelloPharmacist Pharmacist Team. Our sources · Editorial policy

What is this page for?

One answer, for one medication: what supplements and herbal products interact with Guaifenesin, Phenylephrine? Every vitamin, herb, and supplement ingredient we’ve checked against it is on this page, ranked by severity, each linking to the full report for that exact pair.

This page covers supplement interactions only — to check Guaifenesin, Phenylephrine against your other medications, use the drug–drug interaction checker. Educational information from our licensed clinical databases, not medical advice. Our editorial policy

HelloPharmacist Bottom Line
Our Pharmacist Explains
What is this? The interaction data in the HelloPharmacist supplement database is licensed from Natural Medicines Pro by TRC Healthcare (Therapeutic Research). HelloPharmacist pharmacists often add our own analysis and context on top of that licensed data — such as this Bottom Line summary and the notes on individual interaction pages — and any such commentary is noted as ours.

Phenylephrine, the decongestant half of guaifenesin and phenylephrine (Endal, Liquibid-D, Deconsal), tightens blood vessels and raises blood pressure and heart rate, so this list of 62 interacting supplements calls for genuine care. Forty-four of them can pile extra stimulation on top of the drug's own effect, and five rate major, most of them potent herbal stimulants such as ephedra that can send blood pressure into dangerous territory.

Caffeine is the everyday face of the same problem, sitting behind many of the 44 moderate entries; expect jitters and a racing pulse rather than a crisis, though it stacks quickly on a decongestant. The fifth major, activated charcoal, belongs to a different cluster of 17 ingredients that can change how much medicine your body absorbs, and it earns its rating by soaking up drugs in the gut. Only 13 of the 62 sit at the mild end, so most of what is listed below deserves a careful read.

— , Clinical Pharmacist · July 18, 2026

Major 5 Moderate 44 Minor 13 No known interaction 1,390

This box checks one ingredient at a time (like turmeric or magnesium). Taking a supplement product with a whole label of ingredients? Search the product instead — we check every ingredient on it ↓

Top Ingredient Interactions

Guaifenesin, Phenylephrine: Top Interactions at a Glance

The most significant Guaifenesin, Phenylephrine supplement & herbal interactions, colored by severity. Tap any ingredient to open the full report for that pair.

Showing the 12 highest-ranked of 62 interacting ingredients — plus 1,390 more checked with no known interaction. See the complete ranked list.

Start here

The Major Interactions to Know About

The most clinically significant Guaifenesin, Phenylephrine + supplement combinations in our database, best-documented first. Open any card for the full report.

Major Likelihood Probable Activated Charcoal + Guaifenesin, Phenylephrinei

Activated charcoal reduces systemic exposure to many drugs, including those that undergo enterohepatic recirculation, regardless of the route of administration.

Read the full interaction Major Likelihood Probable Ephedra + Guaifenesin, Phenylephrinei

Theoretically, concomitant use might increase the risk for serious adverse effects.

Read the full interaction Major Likelihood Probable Peyote + Guaifenesin, Phenylephrinei

Concomitant use of peyote with stimulant drugs may increase the risk of adverse CNS effects.

Read the full interaction Major Likelihood Probable Rauvolfia Vomitoria + Guaifenesin, Phenylephrinei

Theoretically, concomitant use might cause additive effects.

Read the full interaction Major Likelihood Probable Sida Cordifolia + Guaifenesin, Phenylephrinei

Theoretically, Sida cordifolia might increase the risk of adverse cardiovascular effects when taken with stimulant drugs.

Read the full interaction
The complete list

Every Supplement Checked Against Guaifenesin, Phenylephrine

All 1,452 ingredients in our database, ranked by severity — 62 with a Guaifenesin, Phenylephrine interaction on file and 1,390 with none found. Filter by severity or search any ingredient; hover the for what each ingredient is.

Looking for an interaction with a specific supplement product? Search products instead ↓

Straight answers

Can You Take It With Guaifenesin, Phenylephrine?

One-line answers, one card per combination — scroll through today’s 20 and tap any card for the full report. A different set rotates in daily until every combination has had its turn.

Can you take Marshmallow with Guaifenesin, Phenylephrine?

Minor Usually — this is a minor-rated interaction, generally not clinically significant but worth mentioning to your pharmacist. Theoretically, mucilage in marshmallow might impair absorption of oral drugs.

Full Marshmallow + Guaifenesin, Phenylephrine answer

Can you take N-methyltyramine with Guaifenesin, Phenylephrine?

Minor Usually — this is a minor-rated interaction, generally not clinically significant but worth mentioning to your pharmacist. N-methyltyramine is thought to have stimulant effects.

Full N-methyltyramine + Guaifenesin, Phenylephrine answer

Can you take Octopamine with Guaifenesin, Phenylephrine?

Minor Usually — this is a minor-rated interaction, generally not clinically significant but worth mentioning to your pharmacist. Octopamine is thought to have stimulant effects.

Full Octopamine + Guaifenesin, Phenylephrine answer

Can you take Tyramine with Guaifenesin, Phenylephrine?

Minor Usually — this is a minor-rated interaction, generally not clinically significant but worth mentioning to your pharmacist. Theoretically, taking tyramine with stimulant drugs might increase the risk of adverse cardiovascular effects.

Full Tyramine + Guaifenesin, Phenylephrine answer

Can you take Xanthan Gum with Guaifenesin, Phenylephrine?

Minor Usually — this is a minor-rated interaction, generally not clinically significant but worth mentioning to your pharmacist. Theoretically, xanthan gum can alter the absorption of oral drugs due to its fiber qualities.

Full Xanthan Gum + Guaifenesin, Phenylephrine answer

Can you take Puravive with Guaifenesin, Phenylephrine?

Minor Usually — this is a minor-rated interaction, generally not clinically significant but worth mentioning to your pharmacist. Puravive contains Panax ginseng.

Full Puravive + Guaifenesin, Phenylephrine answer

Can you take Activated Charcoal with Guaifenesin, Phenylephrine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Activated charcoal reduces systemic exposure to many drugs, including those that undergo enterohepatic recirculation, regardless of the rout...

Full Activated Charcoal + Guaifenesin, Phenylephrine answer

Can you take Ephedra with Guaifenesin, Phenylephrine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Theoretically, concomitant use might increase the risk for serious adverse effects.

Full Ephedra + Guaifenesin, Phenylephrine answer

Can you take Peyote with Guaifenesin, Phenylephrine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Concomitant use of peyote with stimulant drugs may increase the risk of adverse CNS effects.

Full Peyote + Guaifenesin, Phenylephrine answer

Can you take Rauvolfia Vomitoria with Guaifenesin, Phenylephrine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Theoretically, concomitant use might cause additive effects.

Full Rauvolfia Vomitoria + Guaifenesin, Phenylephrine answer

Can you take Sida Cordifolia with Guaifenesin, Phenylephrine?

Major Use real caution — this is a major-rated interaction, generally best avoided or used only under close supervision. Theoretically, Sida cordifolia might increase the risk of adverse cardiovascular effects when taken with stimulant drugs.

Full Sida Cordifolia + Guaifenesin, Phenylephrine answer

Can you take Black Tea with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Black Tea + Guaifenesin, Phenylephrine answer

Can you take Caffeine with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Caffeine + Guaifenesin, Phenylephrine answer

Can you take Cocoa with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Cocoa + Guaifenesin, Phenylephrine answer

Can you take Coffee with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Coffee + Guaifenesin, Phenylephrine answer

Can you take Coffee Charcoal with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Coffee charcoal can reduce the absorption of orally administered drugs and should be separated from oral drug administration by at least two...

Full Coffee Charcoal + Guaifenesin, Phenylephrine answer

Can you take Cola Nut with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concomitant use might increase stimulant adverse effects.

Full Cola Nut + Guaifenesin, Phenylephrine answer

Can you take European Mandrake with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, concurrent use might increase absorption of some drugs because of inhibited gastrointestinal (GI) motility caused by European...

Full European Mandrake + Guaifenesin, Phenylephrine answer

Can you take Fever Bark with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, fever bark might increase or decrease the effects of stimulant drugs.

Full Fever Bark + Guaifenesin, Phenylephrine answer

Can you take Glucomannan with Guaifenesin, Phenylephrine?

Moderate Possibly, but carefully — this moderate-rated combination may need monitoring, a dose adjustment, or separated timing. Theoretically, glucomannan may decrease absorption of drugs taken orally.

Full Glucomannan + Guaifenesin, Phenylephrine answer
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 entry links to a full report with the clinical detail, likelihood, evidence level, and citations for that exact combination.
  • Content is reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

How Does Our Interaction Checker Work?

Behind every verdict on this page is a category system. Our source database doesn’t document supplement interactions drug-by-drug — it documents them against groups of medications that behave the same way (for example, “drugs processed by the CYP3A4 liver enzyme” or “blood-thinning medications”).

So the check works in three steps: (1) Guaifenesin, Phenylephrine is classified into the pharmacology categories it belongs to, (2) every supplement interaction documented against any of those categories is inherited by Guaifenesin, Phenylephrine, and (3) each ingredient keeps its own severity, likelihood, and evidence grades from the underlying record. That’s why one supplement can carry several records for one drug — it may interact through more than one category.

Guaifenesin, Phenylephrine sits in 3 interaction categories. Open any one to see what the group means:

Stimulant Drugs 44 ingredients

A pharmacology grouping from our source database: medications in this group share a property that certain supplements are known to interact with, so an interaction documented for the group applies to every drug in it.

44 of the supplement ingredients on this page reach Guaifenesin, Phenylephrine through this category.

Oral Drugs 17 ingredients

A pharmacology grouping from our source database: medications in this group share a property that certain supplements are known to interact with, so an interaction documented for the group applies to every drug in it.

17 of the supplement ingredients on this page reach Guaifenesin, Phenylephrine through this category.

Alpha-Adrenergic Agonists 1 ingredient

A pharmacology grouping from our source database: medications in this group share a property that certain supplements are known to interact with, so an interaction documented for the group applies to every drug in it.

1 of the supplement ingredient on this page reaches Guaifenesin, Phenylephrine through this category.

Check a real product

Take a Supplement Product? Check the Whole Bottle Against Guaifenesin, Phenylephrine

Most supplements are combination products — and the interaction may come from an ingredient you didn’t buy it for. Search any product below (or scan its label) and we’ll check every ingredient on it against Guaifenesin, Phenylephrine.

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Pharmacist Counseling Corner

Guaifenesin, Phenylephrine & Supplements: Common Questions

What supplements interact with Guaifenesin, Phenylephrine?
More than you might expect — 62 in total, though they are far from equal: 5 are rated major, 44 moderate, and 13 minor. The ranked list on this page puts the ones that genuinely matter first, and every entry opens a full report on that exact pair. The highest-ranked right now: Activated Charcoal, Ephedra, Peyote.
Which Guaifenesin, Phenylephrine supplement interactions are the most serious?
The 5 major-rated combinations — led by Activated Charcoal, Ephedra, Peyote, Rauvolfia Vomitoria and Sida Cordifolia — deserve real caution: these are the ones generally best avoided, or used only with your prescriber watching. If you take any of them today, don't panic and don't stop anything abruptly — call your pharmacist first. Jump to the ranked list.
Can I take vitamins or supplements while on Guaifenesin, Phenylephrine?
Usually yes — most people on Guaifenesin, Phenylephrine can take most supplements. The catch is the exceptions, and they aren't always the exotic ones (St. John's Wort trips up more prescriptions than almost anything sold next to it). Look up each ingredient you actually take in the list above, and treat "no known interaction" as a green-ish light, not a guarantee. Try the label scanner or the interaction checker.
Do brands like Amidal have the same supplement interactions as Guaifenesin, Phenylephrine?
Yes — Amidal, Endal, Numonyl Sr, Liquibid-D, Deconsal Sprinkle and other brands all contain Guaifenesin, Phenylephrine, so everything on this page applies to them equally. Interactions belong to the active drug, never to the brand on the box; the same is true of generics.
Where do these interaction ratings come from?
Every rating comes from the Natural Medicines database — the same evidence-graded reference pharmacists and hospitals use — and each interaction carries three separate grades: severity (how bad it can be), likelihood (how well it's documented in studies and case reports), and an evidence level. Our pharmacists review the content; we never let an AI decide an interaction. See how to read the ratings and our editorial policy.
What about Guaifenesin, Phenylephrine and my other medications?
This page covers Guaifenesin, Phenylephrine against supplements and herbal ingredients. Checking Guaifenesin, Phenylephrine against your other prescription or OTC medications is a different tool — our drug interaction checker covers that side. Head to the drug–drug interaction checker.

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

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Sourcing

Where This Data Comes From — and Why You Can Trust It

🧪 Licensed clinical database

Every interaction verdict on this page comes from Natural Medicines Pro (TRC Healthcare / Therapeutic Research) — the same evidence-graded reference used by pharmacists and hospitals. We license this data directly; we do not scrape it, and no AI invents an interaction.

🧑‍⚕️ Pharmacist review

This page is curated and coded by , Clinical Pharmacist, with additional analysis by the HelloPharmacist Pharmacist Team. Editorial commentary is ours; the licensed interaction records are shown as sourced.

🔄 Kept current

Our interaction database refreshes on a weekly cycle, and this page re-checks the live database every time it’s rebuilt — what you see reflects the database as of September 15, 2026.

🔍 Full transparency

How every dataset on this site is sourced, licensed, and updated is documented publicly: our data sources · editorial policy · how we use AI.

Educational information, not medical advice. An interaction being on file does not mean it will happen to you — and absence of one is not proof of safety. Never start or stop a medication or supplement without talking to your pharmacist or doctor.