Drug & supplement interaction

Rauvolfia Vomitoria + Thioridazine

Thioridazine brand name: Mellaril.

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

Thioridazine falls into 2 drug categories that Rauvolfia Vomitoria can interact with; the most serious is rated major. Theoretically, concomitant use might increase the risk of adverse effects.

Read the full interaction report
SeverityMajor
LikelihoodProbable
Interactions2
EvidenceD
What do Severity, Likelihood & Evidence mean?
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Interaction report

Rauvolfia Vomitoria and Thioridazine

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

Why Are There 2 Interactions?

Rauvolfia Vomitoria interacts with whole categories of medication. Thioridazine falls into 2 of those categories, so it can interact with Rauvolfia Vomitoria in 2 different ways. We’ve listed each one below — your overall risk is driven by the most serious of them (Major).

Major

ANTIPSYCHOTIC DRUGS

1 of 2

Why this applies to Thioridazine

Thioridazine falls under ANTIPSYCHOTIC DRUGS — the group Rauvolfia Vomitoria interacts with.

Theoretically, concomitant use might increase the risk of adverse effects.
Concomitant use of neuroleptics with Rauvolfia vomitoria may potentiate the effects of these drugs and the rauwolfia alkaloids.
Severity Major Likelihood Probable Evidence D

Interaction 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..

Dr. Brian Staiger, PharmD, BCPS
Dr. Brian Staiger explains PharmD, Clinical Pharmacist

Here's the concern with pairing Rauvolfia vomitoria and thioridazine. The reserpine and related alkaloids in this root act on the brain and on blood pressure in ways that overlap with what thioridazine already does. So instead of one substance counteracting the other, they can stack on top of each other and push the effects further than expected.

In practice that might mean stronger drowsiness and sedation, feeling lightheaded or dizzy when you stand up (low blood pressure), a slower mood, or movement-related side effects. This is rated a major interaction, though the warning is theoretical and based on how both work rather than on hard studies in people. Thioridazine isn't a prodrug, so the worry is added effects, not reduced ones. Please run this combination by your doctor or pharmacist before mixing them.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines. Trans. S. Klein. Boston, MA: American Botanical Council, 1998.
  2. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
Moderate

CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES

2 of 2

Thioridazine also falls under CYTOCHROME P450 2D6 (CYP2D6) SUBSTRATES.

Theoretically, Rauvolfia vomitoria might increase the levels and clinical effects of CYP2D6 substrates.
Rauvolfia vomitoria contains small amounts of the drug yohimbine. In vitro research shows that yohimbine inhibits CYP2D6 enzyme activity.
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 for thioridazine (Mellaril). Your liver uses an enzyme called CYP2D6 to break this medicine down. Rauvolfia vomitoria contains a bit of yohimbine, and lab studies suggest yohimbine can slow that same enzyme. If it does, thioridazine could clear out of your body more slowly and build up to higher levels than expected.

Why that matters: thioridazine is one of the riskier antipsychotics for the heart. Higher levels can lengthen the heart's QT interval and raise the chance of dangerous rhythm problems, plus more drowsiness, dizziness, and low blood pressure. That said, this warning comes only from test-tube research, not from people, so it's theoretical. Still, given how serious thioridazine's heart risks can be, please run this combo by your doctor or pharmacist first.

Contact Dr. Brian directly if you have additional questions on this interaction
References
  1. VandenBrink, B. M., Foti, R. S., Rock, D. A., Wienkers, L. C., and Wahlstrom, J. L. Prediction of CYP2D6 drug interactions from in vitro data: evidence for substrate-dependent inhibition. Drug Metab Dispos. 2012;40(1):47-53. 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

Rauvolfia Vomitoria Also Interacts With Other Medications

Rauvolfia Vomitoria has 229 major, 523 moderate, 87 minor known drug interactions in our database — the Thioridazine one above is among them. If you take anything else, check it against the full list below.

Major 229 Moderate 523 Minor 87 No known interaction 1,991 (incl. Thioridazine)
Taking anything else?

Check Another of Your Medications Against Rauvolfia Vomitoria

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

From our Q&A

Questions About Rauvolfia Vomitoria or Thioridazine

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

This page covers Rauvolfia Vomitoria only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Thioridazine page lists 168 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), American Hellebore (major), Arsenic (major), Cesium (major) and Ephedra (major).

By severity: 11 major · 125 moderate · 32 minor.

From our pharmacist’s overview on the Thioridazine page

“Thioridazine (Mellaril) is an older antipsychotic already known for disturbing the heart's rhythm, and the supplements that worry me most here do the same thing, stretching the QT interval further. Grapefruit in large amounts sits in that group, alongside ephedra and several other major-rated entries.”

Reviewed by 2 · Jul 18, 2026

Open the Thioridazine interaction page

One more smart check

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

We hold 17 real supplement products containing Rauvolfia Vomitoria, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Rauvolfia Vomitoria. Your product may carry other ingredients that interact with Thioridazine too, on top of Rauvolfia Vomitoria — 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 Rauvolfia Vomitoria and Thioridazine 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 Rauvolfia Vomitoria
Steady interest

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

29 days ago today
Medication Thioridazine
Steady interest

#2,250 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 Rauvolfia Vomitoria

What is Rauvolfia Vomitoria?

  • High blood pressure
  • Anxiety and agitation
  • Sleep problems
  • Mental health symptoms (traditional use)
  • Fever and general ailments

Rauvolfia vomitoria is an African shrub whose root contains powerful alkaloids, including reserpine, that have historically been used for high blood pressure and agitation. Because these compounds can strongly affect blood pressure, mood, and the nervous system, the plant can cause serious side effects and is not a casual supplement. Always talk to a doctor or pharmacist before using it.

Read the full Rauvolfia Vomitoria monograph & all interactions
Medication

About Thioridazine

What Is Thioridazine Used For?

Brand name: Mellaril

Thioridazine Hydrochloride tablets are used for the management of schizophrenia — but only in patients who have already tried at least two other antipsychotic medications without adequate results, either because those drugs didn't work well enough or caused intolerable side effects.

Because thioridazine carries serious heart-rhythm risks, it is considered a last-resort option for schizophrenia, not a first-line treatment. It is not approved for dementia-related psychosis or any other psychiatric condition.

See full Thioridazine drug information
Keep checking

Other Drugs & Rauvolfia Vomitoria

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

229Major
523Moderate
87Minor
1,990No known interaction
229 Major 523 Moderate 87 Minor 1,990 No interaction
Major

229 interactions

Showing 60 of 229 major interactions — see all 229 on the Rauvolfia Vomitoria page.

Moderate

523 interactions

Showing 60 of 523 moderate interactions — see all 523 on the Rauvolfia Vomitoria page.

Minor

87 interactions

Showing 60 of 87 minor interactions — see all 87 on the Rauvolfia Vomitoria page.

No interaction 1,990 drugs checked — show the list

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

Showing the 60 most looked-up of 1,990 medications checked with no known interaction — see the full Rauvolfia Vomitoria list.

See the full Rauvolfia Vomitoria interactions page
See every supplement checked against Thioridazine, 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
Rauvolfia Vomitoria monograph › Uses, safety, and every drug interaction in one place Thioridazine supplement interactions › Every supplement checked against Thioridazine, ranked by severity Thioridazine 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 Rauvolfia Vomitoria and Thioridazine Together: Common Questions

Can you take Rauvolfia Vomitoria with Thioridazine?
This is rated a major interaction, so the combination is best avoided unless your doctor or pharmacist has specifically told you otherwise. Read the full details on this page and confirm with your pharmacist before combining them.
Why are there 2 interactions listed for Rauvolfia Vomitoria and Thioridazine?
Thioridazine belongs to more than one drug category, and Rauvolfia Vomitoria 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 Rauvolfia Vomitoria and Thioridazine interaction?
We rate it Major. This is a clinically significant combination that is generally best avoided, or used only under the direct supervision of your physician or pharmacist.

Written and reviewed by the HelloPharmacist editorial staff. Our editorial policy

Still Have a Question About Thioridazine and Rauvolfia Vomitoria?

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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.