Drug & supplement interaction

Griffonia Simplicifolia + Gabapentin

Gabapentin brand names: Neurontin, Gralise.

Moderate Interaction
The bottom line Moderate

Griffonia Simplicifolia has a moderate interaction with Gabapentin. Theoretically, taking Griffonia simplicifolia seed extract with CNS depressants might increase the risk of additive CNS depression.

Read the full interaction report
SeverityModerate
LikelihoodPossible
EvidenceD
What do Severity, Likelihood & Evidence mean?
Know someone taking this? Share
Interaction report

Griffonia Simplicifolia and Gabapentin

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

Moderate

CNS DEPRESSANTS

Why this applies to Gabapentin

Gabapentin falls under CNS DEPRESSANTS — the group Griffonia Simplicifolia interacts with.

Theoretically, taking Griffonia simplicifolia seed extract with CNS depressants might increase the risk of additive CNS depression.
Griffonia simplicifolia seed extract contains 5-HTP. In clinical trials, 5-HTP has been associated with drowsiness and somnolence.
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 Griffonia simplicifolia and gabapentin: this isn't about one changing how the other is broken down. Instead, it's about overlap. Gabapentin already tends to make people feel drowsy, foggy, or unsteady. Griffonia seed extract supplies 5-HTP, which in studies has caused sleepiness too. Stack them together and those calming effects can simply add up.

In real life, that might mean feeling more groggy than usual, dizzy, or slower to react, which matters if you drive or are prone to falls. I'll be straight with you though: this concern is theoretical, based on how each acts, not on strong human data showing harm. Still, it's worth a quick chat with your pharmacist or doctor before combining them, especially when you first start.

References
  1. Cangiano C, Ceci F, Cancino A, et al. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. Am J Clin Nutr 1992;56:863-7. PubMed
  2. den Boer JA, Westenberg HG. Behavioral, neuroendocrine, and biochemical effects of 5-hydroxytryptophan administration in panic disorder. Psychiatry Res 1990;31:267-78. PubMed
  3. Titus F, Dávalos A, Alom J, Codina A. 5-Hydroxytryptophan versus methysergide in the prophylaxis of migraine. Randomized clinical trial. Eur Neurol 1986;25:327-9. PubMed
  4. De Benedittis G, Massei R. Serotonin precursors in chronic primary headache. A double-blind cross-over study with L-5-hydroxytryptophan vs. placebo. J Neurosurg Sci 1985;29:239-48.
  5. Lemaire PA, Adosraku RK. An HPLC method for the direct assay of the serotonin precursor, 5-hydroxytrophan, in seeds of Griffonia simplicifolia. Phytochem Anal 2002;13(6):333-7.

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

Griffonia Simplicifolia Also Interacts With Other Medications

Griffonia Simplicifolia has 316 moderate known drug interactions in our database — the Gabapentin 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 Griffonia Simplicifolia

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

From our Q&A

Questions About Griffonia Simplicifolia or Gabapentin

These are real questions from readers, answered by the pharmacists at HelloPharmacist — written by a person, not generated from a database. Each one covers Griffonia Simplicifolia or Gabapentin, 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 Gabapentin

This page covers Griffonia Simplicifolia only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Gabapentin page lists 106 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 · 82 moderate · 17 minor.

From our pharmacist’s overview on the Gabapentin page

“Gabapentin (Neurontin, Gralise) calms overactive nerves, which means it already slows your nervous system down, and that is exactly what 78 of the 106 supplements on this list also do. So the dominant risk here is sedation stacked on sedation, extra drowsiness at best and dangerously slowed breathing at worst, and with seven entries ra…”

Reviewed by 2 · Jul 18, 2026

Open the Gabapentin interaction page

One more smart check

Taking Griffonia Simplicifolia as Part of a Dietary Supplement Product? Check It for Interactions

We hold 3 real supplement products containing Griffonia Simplicifolia, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Griffonia Simplicifolia. Your product may carry other ingredients that interact with Gabapentin too, on top of Griffonia Simplicifolia — and those would not show on this page. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Griffonia Simplicifolia and Gabapentin 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 Griffonia Simplicifolia
Top half

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

29 days ago today
Medication Gabapentin
Top 5%

#41 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 Griffonia Simplicifolia

What is Griffonia Simplicifolia?

Griffonia Simplicifolia
  • Low mood
  • Sleep problems
  • Anxiety
  • Appetite control
  • Headaches

Griffonia simplicifolia is a West African shrub whose seeds are a natural source of 5-HTP, a building block of the brain chemical serotonin. Some people use it for mood, sleep, and appetite, but high-quality human evidence is limited, and it should not replace prescribed treatment. Talk with your pharmacist or doctor before using it, especially if you take medicines that affect serotonin.

Read the full Griffonia Simplicifolia monograph & all interactions
Medication

About Gabapentin

What Is Gabapentin Used For?

Brand names: Neurontin, Gralise

Gabapentin (brands include Neurontin, Relgaabi, Gabarone, Gralise, and Horizant) is primarily used to manage postherpetic neuralgia (PHN) — the nerve pain that lingers after a shingles outbreak — in adults. Neurontin, Relgaabi, Gabarone, and gabapentin capsules, tablets, and oral solution are also used as add-on therapy for partial onset seizures (a type of epilepsy) in adults and children aged 3 and older.

Horizant (gabapentin enacarbil extended-release tablet) has two specific approvals: treatment of moderate-to-severe primary restless legs syndrome (RLS) in adults, and management of postherpetic neuralgia in adults. Horizant is not recommended for people who need to sleep during the day and stay awake at night. Gralise is approved only for postherpetic neuralgia and cannot be substituted for other gabapentin products due to its different release profile.

See full Gabapentin drug information
Keep checking

Other Drugs & Griffonia Simplicifolia

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

0Major
316Moderate
0Minor
2,513No known interaction
Moderate

316 interactions

Showing 60 of 316 moderate interactions — see all 316 on the Griffonia Simplicifolia page.

No interaction 2,513 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

Keep exploring
Pharmacist Counseling Corner

Taking Griffonia Simplicifolia and Gabapentin Together: Common Questions

Can you take Griffonia Simplicifolia with Gabapentin?
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 Griffonia Simplicifolia and Gabapentin 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

Still Have a Question About Gabapentin and Griffonia Simplicifolia?

Our pharmacists answer your medication & supplement questions — free.

Ask a pharmacist

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.