Pharmacy Guide
Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.
Pharmacy Guide
Patient leaflets and SmPCs, drug interaction checker, official dosages and NHS pharmacy opening hours — all in one place.
Methenamine hippurate 1 g tablets
⚠ This medicine appears to have been discontinued
The electronic medicines compendium (emc) no longer publishes a Summary of Product Characteristics for this product, which usually means it is no longer marketed in the UK. The patient leaflet below is kept for reference, but the product may not be available.
If you were prescribed this medicine, other products containing Methenamine hippurate may still be available. Do not stop your treatment — ask your pharmacist or GP what to use instead.
What it is and what it is used for
for
Methenamine Tablets is an urinary tract anti-bacterial agent (bactericidal) that is used to prevent relapsing urinary tract infections. Methenamine Tablets is also used during urinary examinations and urinary treatments to reduce the risk of infections. Methenamine Tablets is also given to people who carry urinary tract catheter for a long time. The prophylactic treatment in accordance with these instructions diminishes the risks for new urinary tract infections with repeated painful mictions and bad smelling urine. 2.
What you need to know before you take it
e Methenamine Tablets
Do not use Methenamine Tablets
- if you are allergic to methenamine hippurate or any of the other ingredients of this medicine (listed in section 6)
- if you are hypersensitive to formalin
- if you suffer from renal impairment, are severely dehydrated or have gout
- if you suffer from liver impairment
- if you have a condition called metabolic acidosis (high amount of acidic substances in the body which causes symptoms such as increased heart rate, headache and nausea)
- if you have kidney infection
Other medicines and Methenamine Tablets Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines. Especially tell your doctor if you take any of the following medicines:
- Medicines used for heartburn, since these decrease the effect of Methenamine Tablets by making your urine less acidic
- Medicines called sulphonamides, also known as "sulpha" as they can increase the risk of crystals in the urine (so-called crystalluria) If you are collecting a urine sample, tell the doctor or nurse that you are using Methenamine Tablets, since methenamine hippurate might cause misleading results for some substances, e.g. steroids Methenamine Tablets with food and drink Methenamine Tablets can be taken with or without food and drink. Pregnancy, breast-feeding and fertility If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine. No known risks when used during pregnancy. Ask your doctor if you can use Methenamine Tablets during the pregnancy. Methenamine hippurate is excreted in breast milk but is not likely to influence the child. Discuss with your doctor in case of more than temporary use of Methenamine Tablets during breast-feeding. There is no data available regarding fertility in humans and Methenamine Tablets. Driving and using machines Using this product is not known to affect your ability to drive or to use machines. Methenamine Tablets contains sodium This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially 'sodium-free'. 3.
How to take it
Methenamine Tablets
Always use this medicine exactly as your doctor or pharmacist has told you. Check with your doctor or pharmacist if you are not sure. Recommended dose for adults is 1 tablet 2 times a day. In patients with catheters the dosage may be increased to 1 tablet 3 times a day.
Use in children and adolescents Recommneded dose for children 6-12 years: 1⁄2 tablet twice daily Recommended dose for children older than 12 years: 1 tablet twice daily The tablet can be divided into two equal doses. The tablets may be halved or crushed and taken with water if the patient is unable to swallow whole tablets or other formulations with methenamine hippurate can be used if available.
If you take more Methenamine Tablets than you should The most common symptoms of an overdose are nausea, vomiting and possibly blood in the urine, dizziness and tinnitus. Drink plenty of water. If you forget to take Methenamine Tablets Continue with the treatment according to your doctor's prescription, take your next dose as planned. Do not take a double dose to make up for a forgotten dose. 4.
Possible side effects
Like all medicines, this medicine can cause side effects, although not everybody gets them. Common: may affect up to 1 in 10 people nausea, vomiting, rashes, irritation of the bladder Rare: may affect up to 1 in 1,000 people blood in the urine Not known: frequency cannot be estimated from the available data
diarrhoea, abdominal pains, pruritus
Reporting of side effects If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card System website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine. 5.
How to store it
Methenamine Tablets
Keep this medicine out of the sight and reach of children. Store in the original package in order to protect from moisture. Do not use this medicine after the expiry date which is stated on the carton or label after EXP. The expiry date refers to the last day of that month. Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.
6.
Contents of the pack and other information
What Methenamine Tablets contains The active substance is Methenamine hippurate, 1 gram per tablet. The other ingredients are silica colloidal, povidone, magnesium stearate and croscarmellose sodium. What Methenamine Tablets looks like and contents of the pack White, capsule shaped tablet, break line on both sides. Pack size: 20, 21, 60, 100 and 105 tablets (glass bottle). Not all pack sizes may be marketed.
Marketing Authorisation Holder and Manufacturer: Marketing Authorisation Holder Mercury Pharmaceuticals Ltd. Dashwood House, 69 Old Broad Street, London, EC2M 1QS, United Kingdom Manufacturer EQL Pharma AB Stortorget 1 222 23 Lund Sweden This medicinal product is authorized in the Member States of the EEA under the following names: Denmark: Methenamine hippurate EQL Pharma Norway: Methenamine hippurate EQL Pharma Sweden: Methenamine hippurate EQL Pharma United Kingdom: Methenamine hippurate This leaflet was last revised in January 2024 Other sources of information Detailed information on this medicine is available on the website of MHRA (www.gov.uk/government/organisations/medicines-andhealthcareproducts-regulatory-agency)
Frequently asked questions about Methenamine hippurate 1 g tablets
How do I take Methenamine hippurate 1 g tablets?
Methenamine hippurate 1 g tablets comes as tablet containing 1g. Always follow the dose your doctor or pharmacist has given you, and read the leaflet that comes with the medicine.
What is the active substance in Methenamine hippurate 1 g tablets?
The active substance in Methenamine hippurate 1 g tablets is methenamine hippurate.
Are there equivalent medicines to Methenamine hippurate 1 g tablets?
Medicines with the same active substance, strength and form include: Hiprex 1 g Tablets, Methenamine hippurate 1 g tablets. They are interchangeable only if your prescriber or pharmacist says so.
Where does this information come from?
This leaflet reproduces the patient information leaflet approved for Methenamine hippurate 1 g tablets, as published on the electronic medicines compendium (emc). The version printed inside your medicine’s packaging is the one that applies to you.
Can I get Methenamine hippurate 1 g tablets without a prescription?
Whether a medicine is available over the counter or on prescription only depends on its licence. Check the leaflet, or ask your pharmacist — they can tell you straight away.
About this leaflet
The text above reproduces the patient information leaflet approved for this medicine, restructured for easier reading.
- Source: electronic medicines compendium (emc), Datapharm
- Active substance: methenamine hippurate
- Official document: view the original leaflet on emc →
⚕For healthcare professionals — Summary of Product Characteristics (SmPC)Full SmPC: dosage, interactions, contraindications, warnings+
4.1. Therapeutic indications
Methenamine Tablets is indicated in the prophylaxis of uncomplicated lower urinary tract infections:
1. As long-term prophylactic therapy after initial treatment with appropriate chemotherapeutic agent of recurrent urinary infections.
2. As long-term therapy in the prevention of recurrent cystitis.
3. To provide prophylaxis in patients with indwelling catheters, urine collector etc. and to reduce the incidence of catheter blockage.
4. To provide prophylaxis against the introduction of infection into urinary tract during instrumental procedures.
5. Asymptomatic bacteriuria.
4.2. Posology and method of administration
Posology
Adults: 1 g 2 times a day.
In patients with catheters the dosage may be increased to 1 g three times daily.
Paediatric population:
Children 6-12 years: 0.5 g twice daily.
Children over 12 years: 1 g twice daily.
In cases of alkaline urine pH, supply of acidifying agent could be needed.
Method of administration
For oral administration.
The tablets may be halved or crushed and taken with water if the patient is unable to swallow whole tablets.
4.3. Contraindications
• Hypersensitivity to the active substance or to any of the excipients listed in section 6.1.
• Intolerance or allergic reactions to formalin.
• Renal insufficiency, severe dehydration and gout.
• Hepatic impairment.
• Metabolic acidosis.
• Infection of the kidney.
Methenamine Tablets should not be given concurrently with sulphonamides because of the possibility of crystalluria.
Alkaline agents reduce the effect of methenamine and should be avoided, antacids might cause an increase of urine pH and hence decrease the effect of methenamine.
4.4. Special warnings and precautions for use
None
Sodium
This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially 'sodium-free'.
4.5. Interaction with other medicinal products and other forms of interaction
Alkaline agents reduce the effect of methenamine and should be avoided, antacids might cause an increase of urine pH and hence decrease the effect of methenamine.
Concurrent use with sulphonamides increases the risk of crystalluria.
Depending on analytical procedure, methenamine might affect the determination of steroid, catecholamine and 5-hydroxyindole acetic acid leading to incorrect results.
4.6. Fertility, pregnancy and lactation
Pregnancy
A moderate amount of data on pregnant women (between 300-1000 pregnancies) has not shown signs of malformations or fetal/neonatal toxicity. Animal studies do not indicate reproductive toxicity (see section 5.3). The use of Methenamine Tablets may be considered during pregnancy, if necessary.
Breast-feeding
Methenamine Hippurate is excreted in human milk, but at therapeutic doses of Methenamine Tablets no effects on the breastfed newborns/infants are anticipated.
Fertility
There are no human studies regarding fertility and Methenamine Hippurate.
Animal studies do not indicate direct or indirect harmful effects with respect to reproductive toxicity.
4.7. Effects on ability to drive and use machines
Methenamine Tablets has no or negligible influence on the ability to drive and use machines.
4.8. Undesirable effects
Adverse events frequencies are defined as:
Very common (≥1/l0)
Common (≥1/100 to <1/10)
Uncommon (≥1/1000 to <1/100)
Rare (≥ 1/10 000 to <1/1000)
Very rare (<1/10 000)
Not known (cannot be estimated from the available data).
System Organ Class
Frequency
Common
Rare
Not known
Gastrointestinal disorders
Nausea, vomiting
Diarrhoea, abdominal pains
Skin and subcutaneous tissue disorders
Rashes
Pruritus
Renal and urinary disorders
Irritation of the bladder
Haematuria
Occasionally superinfection with yeast may occur. At high dosage, chemical cystitis leading to dysuria may occur.
Reporting of suspected adverse reactions
Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store.
4.9. Overdose
Toxicity: 8 g to a 2½-year old child resulted in moderate intoxication.
Symptoms: Nausea, vomiting, vertigo, tinnitus and metabolic acidosis may occur. Irritating effect on the urinary tract with albuminuria and haematuria.
Treatment: The treatment is symptomatic and supportive, the use of an anti-emetic and drinking copious quantities of water. Bladder symptoms can be treated by the consumption of copious quantities of water and 2-3 teaspoonfuls of bicarbonate of soda.
💬 Ask about this leaflet
Ask anything about Methenamine hippurate 1 g tablets. The assistant answers only from this leaflet — if the leaflet does not cover it, it will say so. It does not give medical advice.
Answers come from the patient leaflet published on the electronic medicines compendium (emc). They are not medical advice. Ask a pharmacist or your GP if you are unsure. For urgent help call NHS 111, or 999 in an emergency.