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Important Note

The following information is intended to supplement, not substitute for, the expertise and judgment of your physician, pharmacist or other healthcare professional. It should not be construed to indicate that use of the drug is safe, appropriate, or effective for you. Consult your healthcare professional before using this drug.


(meth-EN-uh-meen MAN-duh-late/SO-dee-um FOSS-fate)

COMMON BRAND NAME(S): Uroqid Acid No. 2


This combination medicine is used to treat long term or repeated infections of the urinary tract (kidney, bladder). It works by changing the acid level of the urine; which kills the bacteria causing the infection.

How To Use

Take this medicine by mouth, usually 4 times a day with a full glass (8oz or 240ml) of water, or as directed by your doctor. Long-term use of this medication may be taken less frequently as determined by your doctor. Most fruits, milk and milk products, and antacids containing sodium carbonate or bicarbonate should be avoided while taking this medication. Continue to take this medication until the full-prescribed amount is finished even if symptoms disappear after a few days. Stopping the medication too early may allow bacteria to grow and the infection to return.

Side Effects

Nausea, vomiting, diarrhea, upset stomach, rash, headaches, and difficult or painful urination may occur. If these effects persist or worsen, notify your doctor. Tell your doctor immediately if you have any of these serious side effects: mental/mood changes, seizures, unusual weakness, numbness, swelling or pain of the hands/feet/lips, bone or joint pain, muscle cramps, unusual weight gain, unusual thirst. Tell your doctor immediately if you have any of these unlikely but very serious side effects: fast or irregular heartbeat, trouble breathing, blood in the urine. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor your medical history, especially of: kidney or liver problems, severe dehydration, heart problems (cardiac failure), breathing problems (pulmonary edema), swelling of the hands and feet (peripheral edema), high blood pressure (hypertension), certain hormone imbalances (hypoparathyroidism), certain metabolic conditions (acidosis), pancreatitis, any allergies you may have. Tell your doctor if you have experienced fever or chills with this current urinary infection, you may need other additional medication. This medication contains sodium and phosphorus. If you are currently on a low-sodium, or a phosphate-restricted diet, tell your doctor. Methenamine should be used only when clearly needed during pregnancy. Discuss the risks and benefits with your doctor. This medication is passed into the breast milk. While there have been no reports of harm to nursing infants, consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of all prescription and nonprescription medication you may use, especially: "water pills" (e.g., thiazides diuretics), sulfamethizole, drugs for glaucoma (e.g., acetazolamide), antacids (e.g., sodium bicarbonate), drugs that affect the urine (e.g., alkalinizing agents). This medication may also interact with: certain blood pressure medicines (e.g., guanethidine, hydralazine, and methyldopa), prednisone-like drugs (e.g., corticosteroids), aspirin-like drugs (e.g., salicylates). Do not start or stop any medicine without doctor or pharmacist approval.


If overdose is suspected, contact your local poison control center or emergency room immediately.


Do not share this medication with others. Laboratory and/or medical tests (e.g., sodium levels, urine pH, kidney function) may be performed to monitor your progress. This medication may also cause some laboratory results (e.g., urine estriol, catecholamines) to be incorrect. Consult your doctor or pharmacist for more information.

Missed Dose

If you miss a dose, use it as soon as you remember. If it is near the time of the next dose, skip the missed dose and resume your usual dosing schedule. Do not double the dose to catch up.


Store at room temperature between 36 and 86 degrees F (2 to 30 degrees C) away from light and moisture.