Drug & supplement interaction

Cannabinol (cbn) + Dextromethorphan HBr, Guaifenesin

Dextromethorphan HBr, Guaifenesin brand names: Vicks Formula 44E Cough & Chest Congestion Relief, Pediatric Vicks Formula 44e Cough & Chest Congesti.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Cannabinol (cbn) and Dextromethorphan HBr, Guaifenesin in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

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Interaction report

Cannabinol (cbn) and Dextromethorphan HBr, Guaifenesin

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Dextromethorphan HBr, Guaifenesin and Cannabinol (cbn) in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Cannabinol (cbn) safety at a glance

Cannabinol (cbn) overall Use caution CBN is generally considered mild, but human safety data are limited and product quality varies.
Pregnancy Avoid Cannabis-derived compounds are not considered safe in pregnancy, so avoid CBN.
Breastfeeding Avoid Cannabinoids can pass into breast milk, so avoid CBN while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Dextromethorphan HBr, Guaifenesin and Cannabinol (cbn)? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Dextromethorphan HBr, Guaifenesin

Interactions in our licensed database are recorded against drug classes, not just single drug names. Dextromethorphan HBr, Guaifenesin is filed under 6 classifications — including serotonergic drugs, serotonergic drugs, cytochrome p450 2d6 (cyp2d6) substrates. Cannabinol (cbn) has documented interactions with 5 drug classes — the most serious being cytochrome p450 2b6 (cyp2b6) substrates (moderate), cytochrome p450 2c9 (cyp2c9) inhibitors (moderate) and cytochrome p450 2c9 (cyp2c9) substrates (moderate) — and none of Dextromethorphan HBr, Guaifenesin’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Cannabinol (cbn) Does Interact With Other Medications

Cannabinol (cbn) has 389 moderate known drug interactions in our database — Dextromethorphan HBr, Guaifenesin isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Cannabinol (cbn)

Covers the 2,830 medications we’ve checked against Cannabinol (cbn). Pick one to open its full report.

What to actually watch for

What Cannabinol (cbn) Itself Has Been Linked To

This is not an interaction — nothing below involves Dextromethorphan HBr, Guaifenesin. It is the side-effect record for Cannabinol (cbn) on its own, from the licensed Natural Medicines monograph. If something new turns up after you add Cannabinol (cbn), this list is the first place to look.

  • Drowsiness / Headache Additional detail

    “Orally, cannabinol may cause headache and somnolence.”

    Cannabinol (cbn) · Natural Medicines adverse-effect record, reported in cluster headache.

    1 source cited
    1. 113055. Bonn-Miller MO, Feldner MT, Bynion TM, Eglit GML, Brunstetter M, Kalaba M, Zvorsky I, Peters EN, Hennesy M. A double-blind, randomized, placebo-controlled study of the safety and effects of CBN with and without CBD on sleep quality. Exp Clin Psychopharmac PubMed

Everything above comes from the Natural Medicines adverse-effect record for Cannabinol (cbn) — expand a row for the licensed statement it rests on. We haven’t matched Dextromethorphan HBr, Guaifenesin to its FDA label in our system yet, so we can’t compare its own side-effect list here — the leaflet that comes with your prescription is the authoritative list for Dextromethorphan HBr, Guaifenesin.

Everything else you take

See Every Supplement That Interacts With Dextromethorphan HBr, Guaifenesin

This page covers Cannabinol (cbn) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Dextromethorphan HBr, Guaifenesin page lists 171 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), Lithium (major), St. John's Wort (major) and 1,3-dmaa (moderate).

By severity: 4 major · 125 moderate · 42 minor.

From our pharmacist’s overview on the Dextromethorphan HBr, Guaifenesin page

“A bad cough tends to hit when supplements are already on the counter, and anyone reaching for Vicks Formula 44E (dextromethorphan HBr and guaifenesin) should treat this list with real care, since 4 of its 171 entries carry a major rating. Two themes dominate.”

Reviewed by 2 · Jul 18, 2026

Open the Dextromethorphan HBr, Guaifenesin interaction page

How much people look this up

Where Cannabinol (cbn) and Dextromethorphan HBr, Guaifenesin 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 Cannabinol (cbn)
Steady interest

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

29 days ago today
Medication Dextromethorphan HBr, Guaifenesin
Top half

#1,394 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Cannabinol (cbn) reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 13, 2026. The Cannabinol (cbn) and Dextromethorphan HBr, Guaifenesin records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Cannabinol (cbn)

What is Cannabinol (cbn)?

  • Sleep support
  • Relaxation
  • Pain or discomfort
  • Appetite-related concerns

Cannabinol (CBN) is a minor cannabinoid found in the cannabis plant, often marketed as a 'sleep' aid, but solid human research is very limited. Because it comes from cannabis and product quality varies widely, talk with your pharmacist or doctor before trying it, and avoid it during pregnancy and breastfeeding.

Cannabaceae · Aged cannabis flower and resin (where THC degrades into CBN) · Oils and tinctures, gummies, capsules, vape products, topicals

An interaction check asks whether these two react with each other — it does not ask whether Cannabinol (cbn) is a good idea for someone in your situation. Here is what our Cannabinol (cbn) record says about it on its own.

Cannabinol (cbn): dosing

There is no established, standardized dose for CBN. Research is too limited to recommend a specific milligram amount, and products vary widely in strength and quality.If you choose to try a CBN product, follow the directions on the label and start with the lowest amount.

From our Cannabinol (cbn) monograph — the full record covers uses, side effects and every documented interaction.

Read the full Cannabinol (cbn) monograph & all interactions
Medication

About Dextromethorphan HBr, Guaifenesin

Most-Reported Side Effects for Dextromethorphan HBr, Guaifenesin

From FAERS, the FDA’s public side-effect reporting system (1,675 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Dyspnea 140 reports
Pneumonia 123 reports
Nausea 120 reports
Cough 119 reports
Fatigue 118 reports
Keep checking

Other Drugs & Cannabinol (cbn)

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

0Major
389Moderate
0Minor
2,440No known interaction
Moderate

389 interactions

Showing 60 of 389 moderate interactions — see all 389 on the Cannabinol (cbn) page.

No interaction 2,440 drugs checked — show the list
Evidence & sources

Cannabinol (cbn) References

The 3 references that drive our Cannabinol (cbn) monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Watanabe K, Yamaori S, Funahashi T, Kimura T, Yamamoto I. Cytochrome P450 enzymes involved in the metabolism of tetrahydrocannabinols and cannabinol by human hepatic microsomes. Life Sci. 2007;80(15):1415-9. PubMed
  2. Nasrin S, Watson CJW, Perez-Paramo YX, Lazarus P. Cannabinoid Metabolites as Inhibitors of Major Hepatic CYP450 Enzymes, with Implications for Cannabis-Drug Interactions. Drug Metab Dispos 2021;49(12):1070-1080. PubMed
  3. Bonn-Miller MO, Feldner MT, Bynion TM, Eglit GML, Brunstetter M, Kalaba M, Zvorsky I, Peters EN, Hennesy M. A double-blind, randomized, placebo-controlled study of the safety and effects of CBN with and without CBD on sleep quality. Exp Clin Psychopharmac PubMed

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Cannabinol (cbn) and Dextromethorphan HBr, Guaifenesin Together: Common Questions

Is it safe to take Cannabinol (cbn) with Dextromethorphan HBr, Guaifenesin?
We do not list a known interaction between Cannabinol (cbn) and Dextromethorphan HBr, Guaifenesin. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Cannabinol (cbn) and Dextromethorphan HBr, Guaifenesin combination checked?
Interactions in our licensed database are recorded against drug classes. Dextromethorphan HBr, Guaifenesin is filed under 6 classifications, and Cannabinol (cbn) has documented interactions with 5 drug classes — none of Dextromethorphan HBr, Guaifenesin's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Cannabinol (cbn) interact with any other medications?
Yes. Cannabinol (cbn) has 389 documented drug interactions in our database — Dextromethorphan HBr, Guaifenesin is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Dextromethorphan HBr, Guaifenesin interact with any supplements?
Yes. Dextromethorphan HBr, Guaifenesin has documented interactions with 171 supplements in our database — Cannabinol (cbn) is not one of them. The Dextromethorphan HBr, Guaifenesin interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Dextromethorphan HBr, Guaifenesin and Cannabinol (cbn)?

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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.