Drug & supplement interaction

Fermented Wheat Germ Extract + Isocarboxazid

Isocarboxazid brand name: Marplan.

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

Fermented Wheat Germ Extract has a moderate interaction with Isocarboxazid. Theoretically, concomitant use of fermented wheat germ extract with serotonergic medications may increase the risk of serotonergic adverse effects.

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

Fermented Wheat Germ Extract and Isocarboxazid

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

Moderate

SEROTONERGIC DRUGS

Why this applies to Isocarboxazid

Isocarboxazid falls under SEROTONERGIC DRUGS — the group Fermented Wheat Germ Extract interacts with.

Theoretically, concomitant use of fermented wheat germ extract with serotonergic medications may increase the risk of serotonergic adverse effects.
Animal research shows that fermented wheat germ can increase levels of serotonin in the brain.
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 isocarboxazid (Marplan): it's a strong MAO inhibitor, which means it already raises serotonin levels in your brain by slowing how it gets broken down. Animal studies hint that fermented wheat germ extract can also nudge brain serotonin upward. Stack those two together and, in theory, you could push serotonin too high.

When serotonin climbs too far, people can feel agitated, sweaty, shaky, or restless, with a racing heart or confusion. I want to be honest, though: this concern comes from lab and animal work, not human studies, so it's more of a caution than a proven problem. Because MAO inhibitors are touchy drugs with lots of interactions, please run this supplement by your oncologist, pharmacist, or prescriber before combining the two.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Hu Z, Zhao P, Liao A, et al. Fermented Wheat Germ Alleviates Depression-like Behavior in Rats with Chronic and Unpredictable Mild Stress. Foods 2023;12(5):920. 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

Fermented Wheat Germ Extract Also Interacts With Other Medications

Fermented Wheat Germ Extract has 302 moderate known drug interactions in our database — the Isocarboxazid one above is one of them. If you take anything else, check it against the full list below.

Moderate 302 No known interaction 2,528 (incl. Isocarboxazid)
Taking anything else?

Check Another of Your Medications Against Fermented Wheat Germ Extract

Covers the 2,830 medications we’ve checked against Fermented Wheat Germ Extract. Pick one to open its full report.

Everything else you take

See Every Supplement That Interacts With Isocarboxazid

This page covers Fermented Wheat Germ Extract only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Isocarboxazid page lists 81 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Beer (major), Bitter Orange (major), Brewer's Yeast (major) and Cowhage (major).

By severity: 14 major · 55 moderate · 12 minor.

From our pharmacist’s overview on the Isocarboxazid page

“Isocarboxazid (Marplan) is an MAOI antidepressant, and that drug class carries some of the sharpest supplement and food hazards in the pharmacy, so read this list closely rather than skimming it. Fourteen of the 81 entries rate major, and most of the danger runs through tyramine.”

Reviewed by 2 · Jul 18, 2026

Open the Isocarboxazid interaction page

How much people look this up

Where Fermented Wheat Germ Extract and Isocarboxazid 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 Fermented Wheat Germ Extract
Steady interest

#1,251 of 1,452 supplements looked up here in the last 7 days

29 days ago today
Medication Isocarboxazid
Steady interest

#2,449 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 Fermented Wheat Germ Extract

What is Fermented Wheat Germ Extract?

  • Cancer supportive care (as a complementary product)
  • Immune support
  • General wellness during cancer treatment
  • Antioxidant support
  • Fatigue during illness

Fermented wheat germ extract is a supplement made by fermenting wheat germ with yeast, and it is most often marketed for people going through cancer treatment. While some early research and a few small studies are interesting, the overall evidence is limited and far from conclusive, so it should never replace standard medical care. Talk with your oncologist or pharmacist before using it, since it is a supplement and not an approved treatment.

Read the full Fermented Wheat Germ Extract monograph & all interactions
Medication

About Isocarboxazid

What Is Isocarboxazid Used For?

Brand name: Marplan

Marplan (isocarboxazid) is indicated for the treatment of depression — specifically, major depressive disorder. Because it carries serious risks, it is not a first-choice antidepressant. Marplan is generally reserved for patients who have not responded adequately to other antidepressants.

Clinical trials showed Marplan to be effective in adult outpatients with major depressive disorder, including those whose depression was accompanied by anxiety symptoms such as panic or phobias. Marplan is not approved for use in children or adolescents.

See full Isocarboxazid drug information
Keep checking

Other Drugs & Fermented Wheat Germ Extract

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

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

302 interactions

Showing 60 of 302 moderate interactions — see all 302 on the Fermented Wheat Germ Extract page.

No interaction 2,527 drugs checked — show the list

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

Showing the 60 most looked-up of 2,527 medications checked with no known interaction — see the full Fermented Wheat Germ Extract list.

See the full Fermented Wheat Germ Extract interactions page
See every supplement checked against Isocarboxazid, 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
Fermented Wheat Germ Extract monograph › Uses, safety, and every drug interaction in one place Isocarboxazid supplement interactions › Every supplement checked against Isocarboxazid, ranked by severity Isocarboxazid 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 Fermented Wheat Germ Extract and Isocarboxazid Together: Common Questions

Can you take Fermented Wheat Germ Extract with Isocarboxazid?
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 Fermented Wheat Germ Extract and Isocarboxazid 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 Isocarboxazid and Fermented Wheat Germ Extract?

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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.