• Keep this leaflet. You may need to read it again.
• If you have any further questions, ask your doctor or pharmacist.
• This medicine has been prescribed for you only. Do not pass it on to others. It may harm them, even if their signs of illness are the same as yours.
• If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. See section 4.

1. What Methenamine Tablets is and what it is used for
2. What you need to know before you use Methenamine Tablets
3. How to use Methenamine Tablets
4. Possible side effects
5. How to store Methenamine Tablets
6. Contents of the pack and other information

• 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

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 can be taken with or without food and drink.

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.

Using this product is not known to affect your ability to drive or to use machines.

This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially ‘sodium-free’.

Recommneded dose for children 6-12 years: ½ 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.

The most common symptoms of an overdose are nausea, vomiting and possibly blood in the urine, dizziness and tinnitus. Drink plenty of water.

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.

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.

• The active substance is Methenamine hippurate, 1 gram per tablet.
• The other ingredients are silica colloidal, povidone, magnesium stearate and croscarmellose sodium.

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.

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