Drug & supplement interaction

Cannabidiol (cbd) + Lamotrigine

Lamotrigine brand name: Lamictal.

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

Lamotrigine falls into 2 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
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Cannabidiol (cbd) and Lamotrigine

These two interact in 2 distinct ways. Each one is explained separately below.

Why Are There 2 Interactions?

Cannabidiol (cbd) interacts with whole categories of medication. Lamotrigine falls into 2 of those categories, so it can interact with Cannabidiol (cbd) in 2 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 2

Why this applies to Lamotrigine

Lamotrigine 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 lamotrigine can have a calming, sedating side. When you put them together, those effects may stack up, so you could feel more drowsy, dizzy, or foggy than you would with either one alone. Lamotrigine isn't a prodrug, so this isn't about CBD turning it on or off. It's mainly about overlapping sedation.

I'll be honest with you though, this one is theoretical, based mostly on how higher doses of CBD behave in early research and animal studies. Many people use both without trouble. Still, since lamotrigine controls seizures and mood, I wouldn't change anything on your own. Loop in your pharmacist or doctor first, especially before driving until you know how the combo feels.

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

GLUCURONIDATED DRUGS

2 of 2

Lamotrigine also falls under GLUCURONIDATED DRUGS.

Cannabidiol might increase levels of certain glucuronidated drugs.
In vitro research shows that cannabidiol inhibits uridine diphosphoglucuronosyl transferase (UGT) 1A9 and UGT2B7, enzymes responsible for glucuronidation. Theoretically, this could decrease the clearance and increase levels of glucuronidated drugs.
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 gist with these two together. Your body clears lamotrigine mostly through a process called glucuronidation, handled by enzymes named UGT1A9 and UGT2B7. Lab studies suggest CBD can slow those same enzymes down. If that happens in real life, lamotrigine could clear out a little more slowly and build up in your blood, which may nudge up side effects like dizziness, drowsiness, blurred or double vision, unsteadiness, headache, or nausea.

I want to be honest about the strength of this, though. So far it's only been seen in test-tube research, not in actual patients, so it's more of a theoretical concern than a proven one. Still, lamotrigine is a seizure medicine where steady levels matter, so don't start or change anything on your own. Check in with your pharmacist or doctor first, and tell them right away if you feel newly drowsy or off-balance.

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)

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 Lamotrigine 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. Lamotrigine)
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.

From our Q&A

Questions About Cannabidiol (cbd) or Lamotrigine

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Cannabidiol (cbd) or Lamotrigine, not necessarily both, but if one is close to what you were about to ask it will usually go further than a database entry can:

Not quite your question? Ask our pharmacists directly — it is free, there is no account required, and answers usually come back within 24 hours.

Everything else you take

See Every Supplement That Interacts With Lamotrigine

This page covers Cannabidiol (cbd) only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Lamotrigine page lists 116 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 · 92 moderate · 17 minor.

From our pharmacist’s overview on the Lamotrigine page

“Alcohol, ordinary beer or wine, sits at the top of the interaction list for lamotrigine (Lamictal), with well-documented added sedation, and it sets the tone for a list I would treat with real care. Of the 116 supplements and herbs on file, 78 have sedative effects of their own, so the biggest theme by far is stacked drowsiness and slo…”

Reviewed by 2 · Jul 18, 2026

Open the Lamotrigine interaction page

How much people look this up

Where Cannabidiol (cbd) and Lamotrigine 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

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

29 days ago today
Medication Lamotrigine
Top 5%

#54 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 Lamotrigine

What Is Lamotrigine Used For?

Brand name: Lamictal

Lamotrigine is used to treat several types of seizures in adults and children aged 2 and older — including partial-onset seizures, generalized tonic-clonic (grand mal) seizures, and seizures related to Lennox-Gastaut syndrome. In older teens and adults, it can also be used alone (monotherapy) after transitioning off another seizure medicine.

For adults with bipolar I disorder, lamotrigine is used as a maintenance treatment — meaning it helps delay the return of mood episodes like depression, mania, or mixed states. It is not approved to treat an active manic or mixed episode that's happening right now.

See full Lamotrigine 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 Lamotrigine, 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 Lamotrigine supplement interactions › Every supplement checked against Lamotrigine, ranked by severity Lamotrigine 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 Lamotrigine Together: Common Questions

Can you take Cannabidiol (cbd) with Lamotrigine?
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 2 interactions listed for Cannabidiol (cbd) and Lamotrigine?
Lamotrigine 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 Lamotrigine 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.