Drug & supplement interaction

Cinchona + Mirtazapine

Mirtazapine brand name: Remeron.

Moderate Interaction
The bottom line Moderate

Cinchona has a moderate interaction with Mirtazapine. Theoretically, taking cinchona might inhibit cytochrome P450 2D6 (CYP2D6) and increase levels of drugs metabolized by this enzyme.

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

Cinchona and Mirtazapine

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

Moderate

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES

Why this applies to Mirtazapine

Mirtazapine falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES — the group Cinchona interacts with.

Theoretically, taking cinchona might inhibit cytochrome P450 2D6 (CYP2D6) and increase levels of drugs metabolized by this enzyme.
Quinidine, a constituent of cinchona, inhibits CYP2D6-mediated metabolism in humans.
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 of it. Your body relies partly on an enzyme called CYP2D6 to break down mirtazapine. Cinchona bark contains quinidine, which can block that same enzyme. If that happens, mirtazapine may clear out of your system more slowly and build up a bit higher than usual.

For an active drug like mirtazapine (it's not a prodrug, so more drug means a stronger effect), that could mean more of its typical side effects: drowsiness, grogginess, increased appetite, weight gain, or dizziness. The good news is this concern is theoretical, based on how these compounds behave rather than real-world reports, so I wouldn't panic. Still, cinchona itself carries heart risks, so please check with your pharmacist or doctor before combining them.

References
  1. Hansten PD, Horn JR. Drug Interactions Analysis and Management. Vancouver, WA: Applied Therapeutics Inc., 1997 and updates.
  2. Bramer SL, Suri A. Inhibition of CYP2D6 by quinidine and its effects on the metabolism of cilostazol. Clin Pharmacokinet. 1999;37 Suppl 2:41-51. 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

Cinchona Also Interacts With Other Medications

Cinchona has 3 major, 472 moderate, 16 minor known drug interactions in our database — the Mirtazapine 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 Cinchona

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

From our Q&A

Questions About Cinchona or Mirtazapine

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

This page covers Cinchona only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Mirtazapine page lists 212 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Grapefruit (major), Lithium (major), St. John's Wort (major) and 1,3-dmaa (moderate).

By severity: 4 major · 162 moderate · 46 minor.

From our pharmacist’s overview on the Mirtazapine page

“Depression and poor sleep tend to travel together, which is why people on mirtazapine (Remeron) so often eye herbal mood and sleep remedies, and that overlap is exactly where this list demands real care. Four of the 212 ingredients on file carry a major rating.”

Reviewed by 2 · Jul 18, 2026

Open the Mirtazapine interaction page

One more smart check

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

We hold 12 real supplement products containing Cinchona, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Cinchona. Your product may carry other ingredients that interact with Mirtazapine too, on top of Cinchona — 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 Cinchona and Mirtazapine 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 Cinchona
Top half

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

29 days ago today
Medication Mirtazapine
Top 25%

#519 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 Cinchona

What is Cinchona?

Cinchona
  • Malaria (historical/traditional)
  • Fever
  • Leg cramps and restless legs
  • Digestive upset and loss of appetite
  • Bitter tonic

Cinchona bark is the natural source of quinine and has been used for centuries to treat malaria and fever, but the bark itself is not standardized and can be unpredictable and risky. Modern medicine uses purified, dose-controlled quinine instead, and the supplement form carries real dangers, including serious heart and blood problems. Talk to a pharmacist or doctor before using it, and avoid it during pregnancy.

Read the full Cinchona monograph & all interactions
Medication

About Mirtazapine

What Is Mirtazapine Used For?

Brand name: Remeron

Mirtazapine tablets, mirtazapine orally disintegrating tablets, Remeron, and RemeronsолTab are all indicated for the treatment of major depressive disorder (MDD) in adults. Major depressive disorder involves a persistently low or sad mood most days, often accompanied by loss of interest, sleep changes, fatigue, and difficulty concentrating.

The effectiveness of mirtazapine tablets in maintaining a response for up to 40 weeks after an initial treatment period has also been demonstrated. Patients should be reassessed periodically to determine whether continued treatment is needed.

See full Mirtazapine drug information
Keep checking

Other Drugs & Cinchona

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

3Major
472Moderate
16Minor
2,338No known interaction
Major

3 interactions

Moderate

472 interactions

Showing 60 of 472 moderate interactions — see all 472 on the Cinchona page.

Minor

16 interactions

No interaction 2,338 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 Cinchona and Mirtazapine Together: Common Questions

Can you take Cinchona with Mirtazapine?
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 Cinchona and Mirtazapine 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 Mirtazapine and Cinchona?

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.