Methenamine Hippurate: uses, dosing, side effects & brands
Methenamine Hippurate is a medicine sold in the U.S. under 2 brand and generic names, for bacteriuria, cystitis and escherichia coli infections. Below: what the FDA label says, every product that contains it, what the pills look like, and its recall record.
Key facts
- Treats
- Bacteriuria, Cystitis and Escherichia Coli Infections
- Available as
- Tablet
- Sold as
- 2 products — Hiprex and Urex
- Prescription?
- Prescription only
- Generic available?
- Not in our catalog
How methenamine hippurate is dosed
From the FDA label for Urex (application NDA016151). Other methenamine hippurate products — different forms, different strengths — are dosed differently. Follow the label for the one you were prescribed.
One tablet (1 g) twice daily for adults and children over 12 years of age. One-half tablet or one tablet (0.5 or 1 g) twice daily for children 6 to 12 years of age. The antibacterial activity of Methenamine Hippurate Tablets is greater in acid urine. Therefore, restriction of alkalinizing foods and medications is desirable. If necessary, as indicated by urinary pH and clinical response, supplemental acidification of the urine may be instituted. The efficacy of therapy should be monitored by repeated urine cultures.
Methenamine Hippurate side effects
Adverse effects of Methenamine Hippurate Tablets have been reported in fewer than 3.5% of patients treated. These reactions have included the following, in decreasing order of frequency: nausea, vomiting and rarely pruritus, rash, dysuria. Children have received Methenamine Hippurate Tablets at the recommended dosages as a prophylactic/suppressive regimen after initial treatment of acute episodes of pyuria. Side effects were encountered in only 1.1% of these children.
Who shouldn’t take methenamine hippurate
Methenamine Hippurate Tablets are contraindicated in patients with renal insufficiency, severe hepatic insufficiency, or severe dehydration. It should not be used as the sole therapeutic agent in acute parenchymal infections causing systemic symptoms.
Methenamine Hippurate drug interactions
The concomitant administration of methenamine hippurate and sulfamethizole or sulfathiazole is liable to result in the formation of a precipitate in the urine.
Every methenamine hippurate product we track (2)
Same active ingredient — different manufacturer, form, price and FDA recall record. That last one is what our independent score measures.
| # | Drug | Rating | Type | Form | Generic? | Pharmacy pays | |
|---|---|---|---|---|---|---|---|
| 1 | Not yet rated | Prescription | Tablet | No data | — | View → | |
| 2 | Not yet rated | Prescription | Tablet | No data | — | View → |
What methenamine hippurate pills look like
Imprint codes, colour and shape from the FDA’s labelling data. Match the imprint on your pill — or search any imprint.
How long methenamine hippurate keeps
No methenamine hippurate label we read sets a separate limit for after opening, but they do specify how it must be stored — and the stability behind any date assumes those conditions.
Does methenamine hippurate expire? The in-use limits and storage rules from its labelsMethenamine Hippurate and breastfeeding
From LactMed, the US National Library of Medicine’s Drugs and Lactation Database — quoted, not rewritten.
Full LactMed record for methenamine hippurate: levels in milk, effects in breastfed infants, and the drugs it would consider insteadMethenamine passes into milk in small quantities and appears safe to use, even while nursing a newborn.
National Institute of Child Health and Human Development, record revised January 18, 2021. LactMed states its information is not a substitute for professional judgement.
What people report to the FDA about methenamine hippurate
The FDA Adverse Event Reporting System (FAERS) collects reports from patients and clinicians. It holds 1,266 reports naming methenamine hippurate, and the FDA flagged 58% of those reports as serious. The effects reported most often — leaving out reports about overdose, misuse or the condition being treated, which dominate the raw list for common medicines:
- urinary tract infection159 reports
- nausea85 reports
- diarrhoea83 reports
- fatigue77 reports
- fall74 reports
- headache64 reports
- dizziness57 reports
- pneumonia49 reports
Read these as a signal, not a rate. A report does not mean methenamine hippurate caused the effect — anyone can file one, and many describe people taking several medicines for several conditions. Crucially there is no denominator: FAERS does not record how many people took the drug, so these counts cannot be turned into “X% of patients” — a bigger number often just means a more widely used or more talked-about drug. Duplicates exist, and publicity drives reporting. For what is actually established, read the FDA label section above.
Source: openFDA drug/event (FAERS), retrieved July 25, 2026.
Related calculators
Frequently asked questions
What is methenamine hippurate?
Methenamine Hippurate Tablets are a urinary tract antiseptic drug. Each white, scored tablet contains methenamine hippurate 1g (see HOW SUPPLIED). Methenamine Hippurate Tablets also contain: magnesium stearate, povidone and saccharin sodium.
Can you take methenamine hippurate with other medicines?
It depends on the medicine. We check it against the FDA labels rather than guessing: our interaction checker searches each drug's own label for the other and quotes what it says, naming the section it came from. Run methenamine hippurate against whatever else you take — and remember that a label not naming a drug is not the same as that combination being safe.
What brand names is methenamine hippurate sold under?
We track 2 methenamine hippurate-containing products in the U.S.: Hiprex and Urex. They are the same active ingredient; they differ in form, manufacturer, price and FDA recall record.
What forms does methenamine hippurate come in?
Across the brands we track, methenamine hippurate is currently marketed as tablet, per the FDA's National Drug Code Directory. Each form is dosed differently — follow the label for the exact product you were prescribed.
Is there a generic methenamine hippurate?
We do not currently list a generic-labelled methenamine hippurate product. That does not always mean none exists — it means none appears under a generic name in the FDA data we track. Ask your pharmacist.
Cite this page
- APA
- pharmaranks. (2026, July 24). Methenamine Hippurate: uses, dosing, side effects & brands. https://pharmaranks.com/drugs/methenamine-hippurate
- MLA
- “Methenamine Hippurate: uses, dosing, side effects & brands.” pharmaranks, 24 July 2026, https://pharmaranks.com/drugs/methenamine-hippurate.
We summarise public FDA and NIH sources — for a clinical claim, cite the primary source we link to as well.
Sources: FDA openFDA drug label, National Drug Code Directory, and Enforcement (recall) database. This page reproduces public FDA data and is not medical advice. Dosing is set by your prescriber.
Read the full FDA label for methenamine hippurate on DailyMed (NIH) ↗.