Drug & supplement interaction

Smartweed + Methenamine Hippurate

Methenamine Hippurate brand names: Urex, Hiprex.

No Known Interaction
Medically reviewed by · Updated July 2026 · Pair last verified Sep 27, 2026
The bottom line No known interaction

We found no known interaction between Smartweed and Methenamine Hippurate 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
Facebook Post Reddit Email
On this page
Interaction report

Smartweed and Methenamine Hippurate

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

Why No Interaction Is Listed for Methenamine Hippurate

Interactions in our licensed database are recorded against drug classes, not just single drug names. Methenamine Hippurate is filed under 2 classifications — antibiotic drugs, oral drugs. Smartweed has documented interactions with 1 drug class — the most serious being warfarin (coumadin) (moderate) — and none of Methenamine Hippurate’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 — Methenamine Hippurate isn’t one of them. If you take anything else, check it against the full list below.

Moderate 2 No known interaction 2,828 (incl. Methenamine Hippurate)
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 Methenamine Hippurate’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 Methenamine Hippurate’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. One of them is worth acting on rather than waiting out — marked below.

  • Pain or burning when passing urine Worth acting on
  • Itching
  • Nausea mentioned in 6.6% of FDA reports for Methenamine Hippurate
  • A skin rash
  • Vomiting

From the ADVERSE REACTIONS section of the FDA label for Methenamine Hippurate. Read the label on DailyMed › Where a percentage is shown, it is the share of 1,210 voluntary FDA FAERS reports for Methenamine Hippurate 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 Methenamine Hippurate

This page covers Smartweed only. If you take other supplements — a multivitamin, a sleep aid, something for joints — the Methenamine Hippurate page lists 44 supplements it has a documented interaction with, worst first, each one explained.

The most serious there right now: Activated Charcoal (major), Bacillus Coagulans (moderate), Bacillus Subtilis (moderate), Bifidobacterium Animalis Subsp. Lactis (moderate) and Bifidobacterium Bifidum (moderate).

By severity: 1 major · 33 moderate · 10 minor.

From our pharmacist’s overview on the Methenamine Hippurate page

“Most people taking methenamine hippurate (Hiprex, Urex) use it daily to prevent repeat urinary tract infections, and many also take probiotics, which is where the bulk of this 44-ingredient list sits. Even so, the page deserves real vigilance, because one entry is rated major.”

Reviewed by 2 · Jul 18, 2026

Open the Methenamine Hippurate 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 Methenamine Hippurate, 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 Methenamine Hippurate 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

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

29 days ago today
Medication Methenamine Hippurate
Steady interest

#1,466 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 27, 2026. The Smartweed and Methenamine Hippurate 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 Methenamine

What Is Methenamine Used For?

Brand names: Urex, Hiprex

Methenamine is used to suppress or prevent frequently recurring urinary tract infections (UTIs), including pyelonephritis (kidney infection) and cystitis (bladder infection). It is intended for long-term or ongoing use after another antibiotic has already cleared the active infection — not as a first treatment for a new, acute infection.

Methenamine Mandelate (available as an oral solution and tablet) is also indicated for infected residual urine that can occur with certain neurologic diseases. It is not appropriate as the sole treatment when an infection is causing systemic symptoms like chills and fever.

Most-Reported Side Effects for Methenamine Hippurate

From FAERS, the FDA’s public side-effect reporting system (1,210 reports, all brands). Reports are voluntary and are not proof the drug caused the effect.

Urinary tract infection 163 reports
Diarrhea 81 reports
Nausea 80 reports
Fall 74 reports
Fatigue 74 reports
See full Methenamine 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
2 Moderate 2,827 No interaction
Moderate

2 interactions

No interaction 2,827 drugs checked — show the list

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

Showing the 60 most looked-up of 2,827 medications checked with no known interaction — see the full Smartweed list.

See the full Smartweed interactions page
See every supplement checked against Methenamine Hippurate, ranked by severity
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 Methenamine Hippurate Together: Common Questions

Is it safe to take Smartweed with Methenamine Hippurate?
We do not list a known interaction between Smartweed and Methenamine Hippurate. 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 Methenamine Hippurate combination checked?
Interactions in our licensed database are recorded against drug classes. Methenamine Hippurate is filed under 2 classifications, and Smartweed has documented interactions with 1 drug class — none of Methenamine Hippurate'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 — Methenamine Hippurate 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 Methenamine Hippurate interact with any supplements?
Yes. Methenamine Hippurate has documented interactions with 44 supplements in our database — Smartweed is not one of them. The Methenamine Hippurate interaction page linked on this page lists every one, ranked by severity.

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

Where next

Keep Exploring

Smartweed monograph Uses, safety profile, and every drug interaction in one place Methenamine drug information The full plain-English guide to this medication Methenamine Hippurate supplement interactions Every supplement checked against Methenamine Hippurate, ranked by severity Supplement interaction checker Check any supplement or product against your medications Browse medications A–Z Every drug we’ve checked against herbs & supplements References The 2 citations behind this page Ask a pharmacist Free, personal answer from our licensed team

Still Have a Question About Methenamine Hippurate 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.