Drug & supplement interaction

Cannabidiol (cbd) + Rufinamide

Rufinamide brand name: Banzel.

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

Rufinamide falls into 3 drug categories that Cannabidiol (cbd) can interact with; the most serious is rated moderate. Theoretically, cannabidiol might have additive effects if used with other CNS depressants.

Read the full interaction report
SeverityModerate
LikelihoodPossible
Interactions3
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Cannabidiol (cbd) and Rufinamide

These two interact in 3 distinct ways. Each one is explained separately below.

Why Are There 3 Interactions?

Cannabidiol (cbd) interacts with whole categories of medication. Rufinamide falls into 3 of those categories, so it can interact with Cannabidiol (cbd) in 3 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Moderate).

Moderate

CNS DEPRESSANTS

1 of 3

Why this applies to Rufinamide

Rufinamide falls under CNS DEPRESSANTS — the group Cannabidiol (cbd) interacts with.

Theoretically, cannabidiol might have additive effects if used with other CNS depressants.
Preliminary clinical research, case reports, and animal studies suggest that high dose cannabidiol has sedative and hypnotic effects. Theoretically, concomitant use of cannabidiol with drugs with sedative and anesthetic properties may cause additive therapeutic and adverse effects.
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 simple version: both CBD and rufinamide (Banzel) can calm down activity in the brain. When you take them together, those calming effects can stack up. That might mean more drowsiness, dizziness, trouble concentrating, or feeling unsteady than you'd get from either one alone. For a child or family member taking rufinamide for Lennox-Gastaut seizures, that could look like extra sleepiness or being more wobbly than usual.

I want to be honest about how strong this concern is: it's mostly theoretical, based on how these compounds behave rather than solid head-to-head studies. It doesn't change how rufinamide is broken down. Still, since both touch the brain, it's worth a quick chat with your pharmacist or doctor before combining them, especially with higher CBD doses.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Carlini EA, Cunha JM. Hypnotic and antiepileptic effects of cannabidiol. J Clin Pharmacol 1981;21(8-9 Suppl):417S-27S. PubMed
  2. Monti JM. Hypnoticlike effects of cannabidiol in the rat. Psychopharmacology (Berl) 1977;55(3):263-5. PubMed
  3. Pickens JT. Sedative activity of cannabis in relation to its delta'-trans-tetrahydrocannabinol and cannabidiol content. Br J Pharmacol 1981;72(4):649-56.
  4. Perez-Vilar S, Karami S, Long K, Leishear K. Cannabidiol exposures in the United States, National Poison Data System, July 2014-June 2021. Clin Toxicol (Phila) 2022. PubMed
Moderate

CYTOCHROME P450 3A4 (CYP3A4) INDUCERS

2 of 3

Rufinamide also falls under CYTOCHROME P450 3A4 (CYP3A4) INDUCERS.

Theoretically, CYP3A4 inducers might decrease cannabidiol levels.
Cannabidiol is a substrate of CYP3A4 enzymes. Theoretically, drugs that induce CYP3A4 enzymes might reduce the levels and effects of cannabidiol.
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 know about pairing these two: in this case it's the rufinamide that affects the CBD, not the other way around. Rufinamide gently speeds up a liver enzyme called CYP3A4, and CBD is partly broken down by that same enzyme. So in theory, rufinamide could clear CBD out of your body a little faster, which might make your CBD feel weaker or less effective.

I want to be honest that this is a theoretical concern based on how the drugs work on paper, not something proven in real people, so I wouldn't lose sleep over it. Your rufinamide seizure control shouldn't change because of CBD here. Still, since both can touch the same system and product quality varies, please run any CBD use by your child's neurologist or pharmacist first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Epidiolex (cannabidiol) prescribing information. Greenwich Biosciences, Inc., Carlsbad, CA, 2019. Available at: https://www.epidiolex.com/sites/default/files/EPIDIOLEX_Full_Prescribing_Information.pdf (accessed 5/9/2019)
Moderate

RUFINAMIDE (Banzel)

3 of 3
Cannabidiol might increase rufinamide levels.
In clinical research, concomitant administration of cannabidiol and rufinamide is associated with a modest increase in plasma levels of rufinamide. The mechanism for this interaction is unknown; rufinamide is metabolized via carboxyl esterases. Rufinamide levels stayed within the normal range and did not require dose adjustment. However, caution should be exercised when cannabidiol and rufinamide are taken together.
Severity Moderate Likelihood Likely Evidence B

Well-controlled human studies have demonstrated the likely existence of this interaction.

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

Here's the short version for these two together: in clinical studies, adding CBD nudged rufinamide (Banzel) levels up a bit. Rufinamide is the active drug itself (not a prodrug that needs switching on), so higher blood levels can mean a stronger effect and a greater chance of side effects like sleepiness, dizziness, headache, nausea, or feeling unsteady.

The reassuring part: in the research, rufinamide stayed within its usual range and didn't require a dose change. So this is real but modest. Since both are often used in serious seizure conditions, I'd still loop in your doctor or pharmacist before combining them, and watch for any extra drowsiness or new symptoms. Never adjust seizure medicine on your own.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Gaston TE, Bebin EM, Cutter GR, Liu Y, Szaflarski JP; UAB CBD Program. Interactions between cannabidiol and commonly used antiepileptic drugs. Epilepsia. 2017 Sep;58(9):1586-92. 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

Cannabidiol (cbd) Also Interacts With Other Medications

Cannabidiol (cbd) has 1,050 moderate known drug interactions in our database — the Rufinamide one above is among them. If you take anything else, check it against the full list below.

Moderate 1,050 No known interaction 1,780 (incl. Rufinamide)
Taking anything else?

Check Another of Your Medications Against Cannabidiol (cbd)

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

Everything else you take

See Every Supplement That Interacts With Rufinamide

This page covers Cannabidiol (cbd) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Rufinamide page lists 111 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: 1,4-butanediol (major), Activated Charcoal (major), Beer (major), Gamma-hydroxybutyrate (ghb) (major) and Kava (major).

By severity: 7 major · 89 moderate · 15 minor.

Open the Rufinamide interaction page

How much people look this up

Where Cannabidiol (cbd) and Rufinamide 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 Cannabidiol (cbd)
Top half

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

29 days ago today
Medication Rufinamide
Top half

#771 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 Cannabidiol (cbd)

What is Cannabidiol (cbd)?

  • Anxiety and stress
  • Sleep problems
  • Chronic pain
  • Certain seizure disorders
  • Inflammation

CBD is a compound from the cannabis (hemp) plant that does not cause a 'high.' It has strong evidence only for certain rare seizure disorders (as a prescription drug), while most other popular uses are still backed by limited or early research. Product quality varies a lot, so talk with your pharmacist or doctor before using it, especially if you take other medicines.

Read the full Cannabidiol (cbd) monograph & all interactions
Medication

About Rufinamide

What Is Rufinamide Used For?

Brand name: Banzel

Rufinamide — available as Banzel and generic rufinamide — is used as an add-on treatment (alongside other seizure medicines) for seizures associated with Lennox-Gastaut Syndrome (LGS), a severe type of epilepsy that usually begins in childhood and causes multiple types of seizures.

This indication applies to both the tablet and oral suspension forms, for pediatric patients 1 year of age and older as well as adults.

See full Rufinamide drug information
Keep checking

Other Drugs & Cannabidiol (cbd)

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

0Major
1,050Moderate
0Minor
1,779No known interaction
1,050 Moderate 1,779 No interaction
Moderate

1,050 interactions

Showing 60 of 1,050 moderate interactions — see all 1,050 on the Cannabidiol (cbd) page.

No interaction 1,779 drugs checked — show the list

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

Showing the 60 most looked-up of 1,779 medications checked with no known interaction — see the full Cannabidiol (cbd) list.

See the full Cannabidiol (cbd) interactions page
See every supplement checked against Rufinamide, 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
Cannabidiol (cbd) monograph › Uses, safety, and every drug interaction in one place Rufinamide supplement interactions › Every supplement checked against Rufinamide, ranked by severity Rufinamide drug information › The full plain-English guide to this medication 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 Cannabidiol (cbd) and Rufinamide Together: Common Questions

Can you take Cannabidiol (cbd) with Rufinamide?
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 3 interactions listed for Cannabidiol (cbd) and Rufinamide?
Rufinamide belongs to more than one drug category, and Cannabidiol (cbd) 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 Cannabidiol (cbd) and Rufinamide 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.