Drug & supplement interaction

Cannabinol (cbn) + Sulfadiazine

Sulfadiazine brand name: Sulfadiazine.

Moderate Interaction
The bottom line Moderate

Cannabinol (cbn) has a moderate interaction with Sulfadiazine. Theoretically, CYP2C9 inhibitors might increase the levels and clinical effects of cannabinol.

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

Cannabinol (cbn) and Sulfadiazine

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

Moderate

CYTOCHROME P450 2C9 (CYP2C9) INHIBITORS

Why this applies to Sulfadiazine

Sulfadiazine falls under CYTOCHROME P450 2C9 (CYP2C9) INHIBITORS — the group Cannabinol (cbn) interacts with.

Theoretically, CYP2C9 inhibitors might increase the levels and clinical effects of cannabinol.
In vitro research shows that CYP2C9 enzymes are involved in the 11-hydroxylation of cannabinol. So far, this interaction has not been reported in humans.
Severity Moderate Likelihood Possible Evidence D

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.

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the thing to understand about this pairing: it's really about how sulfadiazine might affect the CBN, not the other way around. Sulfadiazine can block a liver enzyme called CYP2C9, and that same enzyme helps break down cannabinol. So in theory, taking them together could let CBN build up a bit, which might mean stronger or longer-lasting CBN effects like extra drowsiness or grogginess.

I want to be straight with you, though: this is only based on lab studies, not real people, so it's more of a theoretical concern than something we've actually seen happen. Your sulfadiazine itself should still work fine for your infection. Still, since CBN products vary so much, it's worth a quick chat with your pharmacist or doctor before combining them.

References
  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

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

Cannabinol (cbn) Also Interacts With Other Medications

Cannabinol (cbn) has 388 moderate known drug interactions in our database — the Sulfadiazine one above is 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.

Everything else you take

See Every Supplement That Interacts With Sulfadiazine

This page covers Cannabinol (cbn) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Sulfadiazine page lists 107 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Para-aminobenzoic Acid (paba) (major), Siberian Cocklebur (major) and Wine (major).

By severity: 5 major · 91 moderate · 11 minor.

From our pharmacist’s overview on the Sulfadiazine page

“Sulfadiazine treats serious infections like toxoplasmosis, often over long courses, and its list of 107 interacting supplements calls for real care. The most direct problem is PABA, sold as a B-vitamin relative, because it can blunt sulfadiazine's antibacterial effect outright.”

Reviewed by 2 · Jul 18, 2026

Open the Sulfadiazine interaction page

How much people look this up

Where Cannabinol (cbn) and Sulfadiazine 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)
Top half

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

29 days ago today
Medication Sulfadiazine
Steady interest

#1,577 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 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.

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

About Sulfadiazine

What Is Sulfadiazine Used For?

Brand name: Sulfadiazine

Sulfadiazine tablets treat a range of infections. These include chancroid, trachoma, inclusion conjunctivitis, nocardiosis, and certain urinary tract infections caused by susceptible bacteria.

It is also used alongside other medicines for toxoplasmosis encephalitis, malaria from chloroquine-resistant Plasmodium falciparum, acute middle ear infection, and H. influenzae meningitis. It can also help prevent meningococcal meningitis and rheumatic fever recurrences.

See full Sulfadiazine drug information
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
388Moderate
0Minor
2,441No known interaction
Moderate

388 interactions

Showing 60 of 388 moderate interactions — see all 388 on the Cannabinol (cbn) page.

No interaction 2,441 drugs checked — show the list
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

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Pharmacist Counseling Corner

Taking Cannabinol (cbn) and Sulfadiazine Together: Common Questions

Can you take Cannabinol (cbn) with Sulfadiazine?
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.
How serious is the Cannabinol (cbn) and Sulfadiazine 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

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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.