Methenamine Mand-Sod Biphos Oral Warnings
Methenamine Mand-Sod Biphos Oral Uses
This medication is used only to prevent or control returning infections of the bladder and kidneys (urinary tract infections) caused by certain bacteria. This drug is usually prescribed only after the usual antibiotics have been used to eliminate the infection first. Methenamine mandelate belongs to a class of drugs known as antibacterials. It works in the urinary tract by changing into formaldehyde, which kills the bacteria. Methenamine does not treat virus infections (e.g., the common cold). Sodium acid phosphate belongs to a class of drugs known as urinary acidifiers. It helps to keep the urine acid, causing more of the methenamine mandelate to change to formaldehyde.
This antibiotic treats only bacterial infections. It will not work for viral infections (e.g., common cold, flu). Unnecessary use or misuse of any antibiotic can lead to its decreased effectiveness.
How to use Methenamine Mand-Sod Biphos OralTake this medication by mouth, usually 4 times daily after meals and at bedtime or exactly as directed by your doctor.
Dosage is based on your age, medical condition, and response to treatment. To help keep the urine acid while taking this medication, avoid or eat less of most fruits, milk and milk products, and antacids containing sodium carbonate or bicarbonate.
This medication works best when the amount of drug in the urinary tract is kept at a constant level. Therefore, take this drug at evenly spaced intervals. To help you remember, use it at the same times each day.
Do not take more or less of this drug than prescribed or stop taking it even for a short time unless directed to do so by your doctor. Skipping or changing your dose without approval from your doctor may cause the bacterial infection to return, make the bacteria more difficult to treat (resistant), or worsen side effects.
Tell your doctor if symptoms of a urinary tract infection return (e.g., burning, need to urinate frequently).
Methenamine Mand-Sod Biphos Oral Side Effects
Nausea, vomiting, diarrhea, abdominal cramps, uncomfortable urination, and loss of appetite may occur. If any of these effects persist or worsen, tell your doctor or pharmacist promptly.
Remember that your doctor has prescribed this medication because he or she has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.
Tell your doctor immediately if any of these unlikely but serious side effects occur: mouth sores, headache, shortness of breath, ringing in the ears, muscle cramps, body swelling.
Tell your doctor immediately if any of these rare but very serious side effects occur: bone/joint pain, dizziness, confusion, seizures, weakness/heavy feeling in the legs, unusual tiredness or weakness, muscle cramps, numbness/tingling/pain/weakness of hands or feet, numbness or tingling around lips, fast/irregular heartbeat, swelling of feet/lower legs, unusual weight gain, decrease in the amount of urine, unusual thirst.
High doses of methenamine (8 grams daily for 3 to 4 weeks) may cause more severe side effects, including bladder pain/irritation, frequent urination, bloody/pink urine). Tell your doctor immediately if you notice any of these symptoms.
A very serious allergic reaction to this drug is rare. However, seek immediate medical attention if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.
This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.
In the US -
Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.
In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
Methenamine Mand-Sod Biphos Oral Precautions
Before taking methenamine mandelate with sodium acid phosphate, tell your doctor or pharmacist if you are allergic to these medicines; or to formaldehyde; or if you have any other allergies.
This medication should not be used if you have certain medical conditions. Before using this medicine, consult your doctor or pharmacist if you have: kidney problems, severe liver problems (e.g., cirrhosis, chronic hepatitis), severe dehydration, high blood levels of a certain mineral (phosphate).
The sodium phosphate in this medication should be used with caution if you have certain conditions. Tell your doctor if you have any of the following: heart failure, swelling of feet/legs, fluid in the lungs (pulmonary edema), high blood sodium, high blood pressure, toxemia of pregnancy, low parathyroid hormone (hypoparathyroidism), active inflammation of the pancreas (acute pancreatitis).
This product contains a large amount of sodium. This medicine should be used with caution if you are on a low-sodium diet.
Kidney function declines as you grow older. This medication is removed by the kidneys. Therefore, caution is advised when using this drug in the elderly because they may be more sensitive to its side effects.
During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.
This drug passes into breast milk. Since this medication may cause unwanted side effects in your nursing infant, consult your doctor before breast-feeding.
Methenamine Mand-Sod Biphos Oral Interactions
Your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor or pharmacist first.
This drug should not be used with the following medications because very serious interactions may occur: certain sulfa antibiotics (sulfamethizole), thiazide diuretics (e.g., hydrochlorothiazide), carbonic anhydrase inhibitors (e.g., acetazolamide), antacids, urinary alkalinizing agents (e.g., sodium bicarbonate).
If you are currently using any of these medications listed above, tell your doctor or pharmacist before starting this methenamine product.
Before using this medication, tell your doctor or pharmacist of all prescription and nonprescription/herbal products you may use, especially of: high blood pressure medicines (e.g., diazoxide, guanethidine, hydralazine, methyldopa, reserpine), corticosteroids (e.g., corticotropin or mineralocorticoids such as fludrocortisone).
Using this medication with salicylates (e.g., high-dose aspirin) may lead to increased blood salicylate levels. If you currently take high doses of salicylates, tell your doctor because you should be closely monitored to avoid side effects.
This document does not contain all possible interactions. Therefore, before using this product, tell your doctor or pharmacist of all the products you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist.
Methenamine Mand-Sod Biphos Oral Overdose
If overdose is suspected, contact your local poison control center or emergency room immediately. US residents can call the US National Poison Hotline at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES:Do not share this medication with others.
Laboratory and/or medical tests (e.g., liver blood tests, urine bacterial cultures) should be performed periodically to monitor your progress or check for side effects. Consult your doctor for more details.
This medication may interfere with a certain laboratory tests (urine estriol, urine catecholamines, vanilmandelic acid). Make sure that all of your doctors and laboratory personal know that you are taking methenamine.
MISSED DOSE:If you miss a dose, take 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.
STORAGE:Store at room temperature at 77 degrees F (25 degrees C) away from light and moisture. Brief storage between 59-86 degrees F (15-30 degrees C) is permitted. Do not store in the bathroom. Keep all medicines away from children and pets.
Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company for more details about how to safely discard your product.
Information last revised October 2008 Copyright(c) 2008 First DataBank, Inc.










