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Methenamine and sodium salicylate

Generic Name: methenamine and sodium salicylate (meth EN a meen and SOE dee um sa LIS i late)
Brand Name: Cystex Urinary Pain Relief
Dosage Forms: oral tablet (162 mg-162.5 mg)

Medically reviewed by Drugs.com on Nov 17, 2020. Written by Cerner Multum.

What is methenamine and sodium salicylate?

Methenamine helps slow the growth of bacteria. Sodium salicylate is a pain reliever and a nonsteroidal anti-inflammatory drug (NSAID) in a group of drugs called salicylates (sa-LIS-il-ates).

Methenamine and sodium salicylate is a combination medicine that is used to relieve symptoms of bladder infection or irritation, such as painful or burning urination, or feeling an urgent or more frequent need to urinate.

methenamine and sodium salicylate may help slow the progress of a bladder infection. Consult your doctor to make sure you do not need a prescription antibiotic medicine.

Methenamine and sodium salicylate may also be used for purposes not listed in this medication guide.

Important Information

This medicine can increase your risk of fatal heart attack or stroke. Do not use this medicine just before or after heart bypass surgery (coronary artery bypass graft, or CABG). This medicine may also cause stomach or intestinal bleeding, which can be fatal.

Before taking this medicine

An NSAID can increase your risk of fatal heart attack or stroke, even if you don't have any risk factors. Do not use methenamine and sodium salicylate just before or after heart bypass surgery (coronary artery bypass graft, or CABG).

An NSAID may also cause stomach or intestinal bleeding, which can be fatal. These conditions can occur without warning while you are using methenamine and sodium salicylate, especially in older adults.

You should not use this medicine if you are allergic to methenamine, sodium salicylate, or aspirin.

Ask a doctor before using methenamine and sodium salicylate to treat painful or frequent urination if you've never had these symptoms before.

Ask a doctor or pharmacist if this medicine is safe to use if you have ever had:

Ask a doctor before using this medicine if you are pregnant or breastfeeding.

If you are pregnant, you should not take this medicine unless your doctor tells you to. Taking an NSAID during the last 20 weeks of pregnancy can cause serious heart or kidney problems in the unborn baby and possible complications with your pregnancy.

Do not give methenamine and sodium salicylate to a child younger than 12 without medical advice. Do not give this medicine to a child or teenager with a fever, flu symptoms, or chickenpox. Salicylates can cause Reye's syndrome, a serious and sometimes fatal condition in children.

How should I take methenamine and sodium salicylate?

Use exactly as directed on the label, or as prescribed by your doctor.

Use the lowest dose that is effective in treating your condition.

Take this medicine with a full glass of water.

Drink plenty of water each day.

Call your doctor if your symptoms do not improve after 3 days.

Store at room temperature away from moisture, heat, and light.

What happens if I miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking methenamine and sodium salicylate?

Ask a doctor or pharmacist before using other medicines for pain, fever, swelling, or cold/flu symptoms. They may contain ingredients similar to methenamine and sodium salicylate (such as aspirin, ibuprofen, ketoprofen, or naproxen).

Avoid alcohol. Heavy drinking can increase your risk of stomach bleeding.

Methenamine and sodium salicylate side effects

Get emergency medical help if you have signs of an allergic reaction: sneezing, runny or stuffy nose; wheezing or trouble breathing; hives; swelling of your face, lips, tongue, or throat.

Stop using methenamine and sodium salicylate and call your doctor at once if you have:

  • ringing in your ears;

  • a light-headed feeling, like you might pass out;

  • new or worsening stomach pain; or

  • bloody or tarry stools, coughing up blood or vomit that looks like coffee grounds.

Less serious side effects may be more likely, and you may have none at all.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect methenamine and sodium salicylate?

Ask a doctor or pharmacist before using methenamine and sodium salicylate with any other medications, especially:

This list is not complete. Other drugs may affect methenamine and sodium salicylate, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

More about methenamine / sodium salicylate

Consumer resources

Other brands: Cystex Urinary Pain Relief

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