Drug & supplement interaction

Peyote + Guaifenesin, Phenylephrine

Guaifenesin, Phenylephrine brand names: Amidal, Endal, Numonyl Sr, Liquibid-D, Deconsal Sprinkle, and others.

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

Peyote has a major interaction with Guaifenesin, Phenylephrine. Concomitant use of peyote with stimulant drugs may increase the risk of adverse CNS effects.

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

Peyote and Guaifenesin, Phenylephrine

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

Major

STIMULANT DRUGS

Why this applies to Guaifenesin, Phenylephrine

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

Concomitant use of peyote with stimulant drugs may increase the risk of adverse CNS effects. Some CNS stimulants include nicotine, cocaine, sympathomimetic amines, and amphetamines.
Severity Major 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

The piece of this combo that matters is the phenylephrine, which is a decongestant that mildly stimulates the body, much like adrenaline. It can nudge up your heart rate and blood pressure. The guaifenesin part is just an expectorant that loosens mucus and doesn't really play into this concern.

Peyote (through its active compound, mescaline) can also rev up the nervous system. Stacking it with a stimulant like phenylephrine could, in theory, add together and raise the chance of effects like a racing or pounding heart, higher blood pressure, jitteriness, restlessness, or trouble sleeping. I'll be honest, this warning is based on how these things work on paper, not on solid studies. Still, since peyote itself is a controlled substance and not a safe self-treatment, the smartest move is to run this by your pharmacist or doctor first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Martindale W. Martindale the Extra Pharmacopoeia. Pharmaceutical Press, 1999.
  2. Ellenhorn MJ, et al. Ellenhorn's Medical Toxicology: Diagnoses and Treatment of Human Poisoning. 2nd ed. Baltimore, MD: Williams & Wilkins, 1997.

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

Peyote Also Interacts With Other Medications

Peyote has 171 major, known drug interactions in our database — the Guaifenesin, Phenylephrine one above is one of them. If you take anything else, check it against the full list below.

Major 171 No known interaction 2,659 (incl. Guaifenesin, Phenylephrine)
Taking anything else?

Check Another of Your Medications Against Peyote

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

Everything else you take

See Every Supplement That Interacts With Guaifenesin, Phenylephrine

This page covers Peyote only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Guaifenesin, Phenylephrine 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), Rauvolfia Vomitoria (major), Sida Cordifolia (major) and 1,3-dmaa (moderate).

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

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

“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…”

Reviewed by 2 · Jul 18, 2026

Open the Guaifenesin, Phenylephrine interaction page

How much people look this up

Where Peyote and Guaifenesin, Phenylephrine 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 Peyote
Steady interest

#1,108 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Guaifenesin, Phenylephrine
Steady interest

#1,684 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 Peyote

What is Peyote?

  • Traditional and religious ceremonies
  • Spiritual or visionary experiences
  • Folk use for pain and fatigue
  • Folk use for fever and skin conditions

Peyote is a small spineless cactus that contains mescaline, a powerful hallucinogen. It is a federally controlled substance in the United States (with a narrow exemption for certain Native American religious use), is not a safe or proven dietary supplement, and should not be used for self-treatment.

Read the full Peyote monograph & all interactions
Keep checking

Other Drugs & Peyote

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

171Major
0Moderate
0Minor
2,658No known interaction
171 Major 2,658 No interaction
Major

171 interactions

Showing 60 of 171 major interactions — see all 171 on the Peyote page.

No interaction 2,658 drugs checked — show the list

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

Showing the 60 most looked-up of 2,658 medications checked with no known interaction — see the full Peyote list.

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

Can you take Peyote with Guaifenesin, Phenylephrine?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
How serious is the Peyote and Guaifenesin, Phenylephrine interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

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

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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.