Generic Name: Methenamine

  • What is Urex?

    Urex is used to treat urinary tract infections when long-term therapy is required.

  • What is the most important information I should know about Urex?

    Urex should only be used to treat or prevent infections that are strongly suspected or proved to be caused by bacteria. Antibacterial drugs, including Urex, do not treat viral infections.

    If you take doses larger than recommended it can cause bladder irritation and painful and frequent urination.

    Skipping doses or not completing the full course of therapy may decrease the effectiveness of Urex and increase the likelihood that bacteria will develop resistance, making it harder to treat infections with Urex or other antibacterial drugs in the future.

  • Who should not take Urex?

    Do not take Urex if you have kidney or liver problems or severe dehydration.

  • What should I tell my doctor before I take the first dose of Urex?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with Urex. Also talk to your doctor about your complete medical history, especially if have any problems with your kidneys or liver.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.

    Adults and children ≥12 years: 1 gram (1 tablet) twice daily.

    Children 6-12 years: 1 gram (1 tablet) or 0.5 gram (1/2 tablet) twice daily.

  • How should I take Urex?

    Take Urex with a full glass of water and with food.

  • What should I avoid while taking Urex?

    Avoid alkalinizing foods, such as almonds, citrus fruits, dairy products, and molasses.

  • What are possible food and drug interactions associated with Urex?

    If Urex is used with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining Urex with sulfamethizole.

  • What are the possible side effects of Urex?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects may include: nausea, vomiting, rash, pain while urinating

  • Can I receive Urex if I am pregnant or breastfeeding?

    Avoid Urex during pregnancy and while breastfeeding.

  • What should I do if I miss a dose of Urex?

    If you miss a dose, take it as soon as you remember. However, if it is almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once.

  • How should I store Urex?

    Store at room temperature.

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I'm Kristen Dore, PharmD. Welcome to PDR Health!

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