Drug & supplement interaction

Smartweed + Thioridazine

Thioridazine brand name: Mellaril.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Smartweed and Thioridazine in our sources. Absence of a documented interaction is not the same as proven safety, and does not guarantee one does not exist. Do not start, stop, or change a medication or supplement based on this page; confirm with your pharmacist or doctor first.

Know someone taking this? Share
Interaction report

Smartweed and Thioridazine

We checked these two against our interaction database. Here is what we found.

No Known Interaction Found

We did not find a documented interaction between Thioridazine and Smartweed in our sources. This does not guarantee that the combination is completely free of risk — there is often limited research on supplements and herbal products, especially around drug interactions.

If you decide to take both, the practical routine is simple: add one new thing at a time and note the date you started it. If the combination is going to disagree with you, it usually shows in the first days to a couple of weeks — and a start date turns “I’ve been feeling off” into something a pharmacist can actually work with. Do not stop a prescribed medicine on your own.

Always talk with your pharmacist or doctor before making changes to your medications or supplements, particularly if you take several medications or have an ongoing health condition.

Smartweed safety at a glance

Smartweed overall Use caution There is little modern safety data, so use cautiously and talk to a healthcare provider first.
Pregnancy Avoid Traditionally used to affect menstruation and the uterus, so avoid during pregnancy.
Breastfeeding Avoid There is not enough safety information, so it is best to avoid while breastfeeding.

Safety guidance is general; always confirm with your pharmacist or doctor for your situation.

Still wondering about combining Thioridazine and Smartweed? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Thioridazine

Interactions in our licensed database are recorded against drug classes, not just single drug names. Thioridazine is filed under 10 classifications — including phenothiazines, antipsychotic drugs, cytochrome p450 2c19 (cyp2c19) substrates. Smartweed has documented interactions with 1 drug class — the most serious being warfarin (coumadin) (moderate) — and none of Thioridazine’s classifications are among them.

Classification data comes from our licensed Natural Medicines dataset. A medication can belong to classes beyond those recorded there, so this describes how the check was run — it is not a safety guarantee.

Keep it in perspective

Smartweed Does Interact With Other Medications

Smartweed has 2 moderate known drug interactions in our database — Thioridazine isn’t one of them. If you take anything else, check it against the full list below.

Taking anything else?

Check Another of Your Medications Against Smartweed

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

What to actually watch for

What Thioridazine’s Own FDA Label Lists

This is not an interaction — none of it involves Smartweed. These are the most notable effects listed in the ADVERSE REACTIONS section of Thioridazine’s own FDA label, for the medication by itself. Knowing the drug’s own list makes it easier to work out the likely cause if something new turns up while you take both. 10 of them are worth acting on rather than waiting out — marked below.

  • A bowel blockage Worth acting on
  • Yellowing of the skin or eyes Worth acting on
  • Wheezing Worth acting on
  • An irregular heartbeat Worth acting on
  • Confusion Worth acting on
  • Low mood Worth acting on
  • A low platelet count Worth acting on
  • Anemia Worth acting on
  • A low white blood cell count Worth acting on
  • Liver problems Worth acting on

Showing the 10 most notable of 33 label-listed effects — ranked by how unusual each one is across medicines generally, with serious effects weighted up.

From the ADVERSE REACTIONS section of the FDA label for Thioridazine. Read the label on DailyMed › Smartweed’s licensed record lists no adverse effects our clinical vocabulary could match, so there is no Smartweed side to compare — that is a limit of the record, not a statement that Smartweed has no side effects.

From our Q&A

Questions About Smartweed 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 Smartweed 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 Smartweed 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 Smartweed as Part of a Dietary Supplement Product? Check It for Interactions

We hold 4 real supplement products containing Smartweed, each one broken down to its full ingredient list — and combination products often carry several ingredients besides Smartweed. Even though Smartweed itself has no known interaction with Thioridazine, another ingredient on your label might. Find your product and we’ll check every ingredient on its label:

How much people look this up

Where Smartweed 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 Smartweed
Steady interest

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

29 days ago today
Medication Thioridazine
Top half

#1,309 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.

Where does our data come from?
  • Source: the Natural Medicines (TRC Healthcare) clinical database — the evidence-graded professional reference for herb & supplement interactions.
  • Citation library: 103,510 references behind our interaction content, 65,311 of them resolved to verified PubMed/DOI sources. See every Smartweed reference on this page ↓
  • Freshness: we automatically re-check this combination every week — this pair was last verified September 20, 2026. The Smartweed and Thioridazine records this page draws on were last updated July 10, 2026.
  • What “no known interaction” means: no documented interaction in the sources above — not a guarantee of safety. Supplements are studied far less than prescription drugs, so we say exactly what the evidence supports, and nothing more.
Data structure & sourcing designed and verified by .
Supplement

About Smartweed

What is Smartweed?

Smartweed
  • Digestive upset
  • Minor skin irritation
  • Heavy menstrual bleeding (traditional)
  • Wound and bleeding (traditional topical use)
  • Antioxidant and anti-inflammatory support

Smartweed (Persicaria hydropiper) is a peppery wetland plant with a long history in traditional medicine for digestive complaints, bleeding, and skin problems. Modern human studies are very limited, so its benefits are not well proven. Because safety data are thin, it's best to use cautiously and avoid it during pregnancy and breastfeeding.

Persicaria hydropiper · Polygonaceae · Aerial parts (leaves, stems, and flowering tops); sometimes the whole plant · Tea, tincture, liquid extract, dried herb, and topical preparations

An interaction check asks whether these two react with each other — it does not ask whether Smartweed is a good idea for someone in your situation. Here is what our Smartweed record says about it on its own.

Smartweed: dosing

There is no well-established or standardized dose for smartweed. Because it has not been carefully studied in people, experts cannot recommend a safe and effective amount.If you choose to use a product, follow the directions on the label and do not exceed them.

From our Smartweed monograph — the full record covers uses, side effects and every documented interaction.

Read the full Smartweed 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 & Smartweed

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

0Major
2Moderate
0Minor
2,827No known interaction
Moderate

2 interactions

No interaction 2,827 drugs checked — show the list
Evidence & sources

Smartweed References

The 2 references that drive our Smartweed monograph and interaction data, from the evidence-graded Natural Medicines (TRC Healthcare) database. Citations with a link open the study on PubMed or the publisher’s site.

  1. Gruenwald J, Brendler T, Jaenicke C. PDR for Herbal Medicines. 1st ed. Montvale, NJ: Medical Economics Company, Inc., 1998.
  2. Brinker F. Herb Contraindications and Drug Interactions. 2nd ed. Sandy, OR: Eclectic Medical Publications, 1998.

Medication overviews come from MedlinePlus (NIH); supplement label data from the NIH Dietary Supplement Label Database. Content is written and reviewed by licensed HelloPharmacist pharmacists — see our data sources and editorial standards.

Pharmacist Counseling Corner

Taking Smartweed and Thioridazine Together: Common Questions

Is it safe to take Smartweed with Thioridazine?
We do not list a known interaction between Smartweed and Thioridazine. That does not guarantee the combination is risk-free, so confirm with your pharmacist or doctor — especially if you take other medications or have a health condition.
How was the Smartweed and Thioridazine combination checked?
Interactions in our licensed database are recorded against drug classes. Thioridazine is filed under 10 classifications, and Smartweed has documented interactions with 1 drug class — none of Thioridazine's classifications are among them. A medication can belong to classes beyond those recorded in our dataset, so this describes how the check was run rather than guaranteeing safety.
Does Smartweed interact with any other medications?
Yes. Smartweed has 2 documented drug interactions in our database — Thioridazine is simply not one of them. If you take anything else, it is worth checking each one; they are all listed on this page.
Does Thioridazine interact with any supplements?
Yes. Thioridazine has documented interactions with 168 supplements in our database — Smartweed is not one of them. The Thioridazine interaction page linked on this page lists every one, ranked by severity.

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

Still Have a Question About Thioridazine and Smartweed?

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.