Drug & supplement interaction

Smartweed + Leucovorin Calcium

Leucovorin Calcium brand name: Wellcovorin.

No Known Interaction
The bottom line No known interaction

We found no known interaction between Smartweed and Leucovorin Calcium 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.

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Interaction report

Smartweed and Leucovorin Calcium

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 Leucovorin Calcium 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 Leucovorin Calcium and Smartweed? Ask Dr. Brian Staiger, PharmD, BCPS directly ›
How we checked

Why No Interaction Is Listed for Leucovorin Calcium

Interactions in our licensed database are recorded against drug classes, not just single drug names. Leucovorin Calcium is filed under a single classification — oral drugs. Smartweed has documented interactions with 1 drug class — the most serious being warfarin (coumadin) (moderate) — and none of Leucovorin Calcium’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 — Leucovorin Calcium 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 Leucovorin Calcium’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 Leucovorin Calcium’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. 5 of them are worth acting on rather than waiting out — marked below.

  • A low white blood cell count Worth acting on mentioned in 5.8% of FDA reports for Leucovorin Calcium
  • A low platelet count Worth acting on
  • Kidney problems Worth acting on
  • Hives Worth acting on
  • A higher chance of infection Worth acting on
  • Mouth irritation or sores
  • Hair loss
  • Reduced appetite
  • Constipation
  • Diarrhea mentioned in 9.5% of FDA reports for Leucovorin Calcium

Showing the 10 most notable of 14 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 Leucovorin Calcium. Read the label on DailyMed › Where a percentage is shown, it is the share of 19,003 voluntary FDA FAERS reports for Leucovorin Calcium that mention that effect — a reporting proportion, not an incidence rate and not evidence the drug caused it. 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.

Everything else you take

See Every Supplement That Interacts With Leucovorin Calcium

This page covers Smartweed only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Leucovorin Calcium page lists 17 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Coffee Charcoal (moderate), European Mandrake (moderate), Glucomannan (moderate) and Guar Gum (moderate).

By severity: 1 major · 7 moderate · 9 minor.

Open the Leucovorin Calcium 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 Leucovorin Calcium, 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 Leucovorin Calcium 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
Top half

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

29 days ago today
Medication Leucovorin Calcium
Top 25%

#483 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 13, 2026. The Smartweed and Leucovorin Calcium 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 Leucovorin

What Is Leucovorin Used For?

Brand name: Wellcovorin

Leucovorin is used to reduce the harmful effects of methotrexate when the body is slow to clear it, and to counteract accidental overdoses of drugs that block folic acid (called folic acid antagonists or DHFR inhibitors). It is also used to treat cerebral folate transport deficiency (FOLR1-CFTD), a rare genetic condition that prevents the brain from receiving enough folate.

The injectable forms — including leucovorin calcium injection and Vykoura — are additionally approved for rescue after high-dose methotrexate therapy, for treatment of megaloblastic anemia (a type of anemia caused by low folic acid) when oral treatment isn't possible, and for use alongside fluorouracil in treating metastatic colorectal cancer. Leucovorin calcium injection is specifically indicated for rescue after high-dose methotrexate in osteosarcoma.

Most-Reported Side Effects for Leucovorin Calcium

From FAERS, the FDA’s public side-effect reporting system (19,003 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Diarrhea 1,799 reports
Nausea 1,388 reports
Vomiting 1,135 reports
Neutropenia 1,094 reports
Fever 1,011 reports
See full Leucovorin 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 Leucovorin Calcium Together: Common Questions

Is it safe to take Smartweed with Leucovorin Calcium?
We do not list a known interaction between Smartweed and Leucovorin Calcium. 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 Leucovorin Calcium combination checked?
Interactions in our licensed database are recorded against drug classes. Leucovorin Calcium is filed under 1 classification, and Smartweed has documented interactions with 1 drug class — none of Leucovorin Calcium'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 — Leucovorin Calcium 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 Leucovorin Calcium interact with any supplements?
Yes. Leucovorin Calcium has documented interactions with 17 supplements in our database — Smartweed is not one of them. The Leucovorin Calcium 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 Leucovorin Calcium and Smartweed?

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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.