Drug & supplement interaction

Nutmeg + Olanzapine

Olanzapine brand name: Zyprexa.

Moderate Interaction
The bottom line Moderate

Nutmeg has a moderate interaction with Olanzapine. Theoretically, nutmeg might decrease levels of drugs metabolized by CYP1A2.

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

Nutmeg and Olanzapine

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

Moderate

CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES

Why this applies to Olanzapine

Olanzapine falls under CYTOCHROME P450 1A2 (CYP1A2) SUBSTRATES — the group Nutmeg interacts with.

Theoretically, nutmeg might decrease levels of drugs metabolized by CYP1A2.
Animal research suggests that intraperitoneal injections of myristicin, a constituent of nutmeg, can induce CYP1A2.
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: your body relies on a liver enzyme called CYP1A2 to clear olanzapine (Zyprexa) out of your system. Some lab and animal research hints that a compound in nutmeg, called myristicin, might speed that enzyme up. If that happened in people, your body could break down olanzapine a little faster, which in theory might make it work less well. For a medication you take to keep symptoms of schizophrenia or bipolar disorder steady, you wouldn't want it quietly losing strength.

That said, I want to be honest about the evidence: this is theoretical and only based on animal studies. Normal cooking amounts of nutmeg almost certainly won't matter. Just avoid large 'medicinal' nutmeg doses (they can be toxic anyway), and check with your pharmacist or doctor if you're unsure.

References
  1. Jeong HG, Yun CH. Induction of rat hepatic cytochrome P450 enzymes by myristicin. Biochem Biophys Res Commun 1995;217:966-71. 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

Nutmeg Also Interacts With Other Medications

Nutmeg has 527 moderate known drug interactions in our database — the Olanzapine 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 Nutmeg

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

From our Q&A

Questions About Nutmeg or Olanzapine

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

This page covers Nutmeg only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Olanzapine page lists 160 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Indian Snakeroot (major), Lithium (major), Rauvolfia Vomitoria (major) and 1,3-dmaa (moderate).

By severity: 4 major · 118 moderate · 38 minor.

From our pharmacist’s overview on the Olanzapine page

“Olanzapine (Zyprexa) is an antipsychotic prescribed for schizophrenia and bipolar disorder, and adding supplements to it warrants genuine care. Four of the 160 ingredients on file rate major, and those four deserve your attention before anything else: lithium supplements raise the risk of serotonin syndrome, activated charcoal can trap…”

Reviewed by 2 · Jul 18, 2026

Open the Olanzapine interaction page

One more smart check

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

We hold 182 real supplement products containing Nutmeg, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Nutmeg. Your product may carry other ingredients that interact with Olanzapine too, on top of Nutmeg — 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 Nutmeg and Olanzapine 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 Nutmeg
Top half

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

29 days ago today
Medication Olanzapine
Top half

#1,269 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 Nutmeg

What is Nutmeg?

Nutmeg
  • Digestive upset
  • Diarrhea
  • Sleep and relaxation
  • Pain and inflammation
  • Flavoring spice

Nutmeg is a popular cooking spice that has long been used in traditional medicine for digestion and other complaints, but there is little solid human research to support its medicinal use. In normal cooking amounts it is generally safe, but larger "medicinal" doses can cause serious poisoning, so it should never be taken in high amounts.

Read the full Nutmeg monograph & all interactions
Medication

About Olanzapine

What Is Olanzapine Used For?

Brand name: Zyprexa

Olanzapine is used for schizophrenia and for manic or mixed episodes of bipolar I disorder, including long-term maintenance treatment. It can also be added to lithium or valproate for manic or mixed episodes. Oral olanzapine is approved for adults and for teens ages 13 to 17.

Olanzapine for injection (intramuscular) is used for sudden agitation linked to schizophrenia or bipolar I mania in adults. Zyprexa Relprevv, a long-acting injection, is used only for schizophrenia. Oral olanzapine taken together with fluoxetine is used for depressive episodes of bipolar I disorder, as covered in the Symbyax labeling.

See full Olanzapine drug information Olanzapine NDC codes and packages
Keep checking

Other Drugs & Nutmeg

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

0Major
527Moderate
0Minor
2,302No known interaction
Moderate

527 interactions

Showing 60 of 527 moderate interactions — see all 527 on the Nutmeg page.

No interaction 2,302 drugs checked — show the list

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

Showing the 60 most looked-up of 2,302 medications checked with no known interaction — see the full Nutmeg 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 Nutmeg and Olanzapine Together: Common Questions

Can you take Nutmeg with Olanzapine?
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 Nutmeg and Olanzapine 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 Olanzapine and Nutmeg?

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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.