Find & Manage Your Patient Assistance Programs
Estimated patient savings $600,000,000.00

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.


(poh-TASS-ee-um/SO-dee-um FOSS-fate)



This medication makes the urine more acidic. It is used to prevent formation of calcium kidney stones and to reduce odor and skin irritation caused by high ammonia urine. It may also be used with certain antibiotics to make them more effective.

How To Use

The usual dosage is one tablet four times a day with a full glass (8 oz or 240 ml) of water. The dosage may be increased to one tablet every two hours, however, no more than eight tablets should be taken in a 24 hour period. Do not lie down for 30 minutes after taking this medication. Take this medication as prescribed. Do not increase your dose or take this more often without your doctor's approval.

Side Effects

Stomach upset, loose stools or headache may occur the first few days as your body adjusts to the medication. If these effects continue or become bothersome, inform your doctor. Notify your doctor if you develop: nausea, vomiting, stomach pain, fluid retention, convulsions, unusual weakness, mental confusion, dizziness, muscle cramps, a rapid or irregular heartbeat, breathing trouble, tingling or numbness of the hands or feet. When this medication is started, there is a chance an old kidney stone may be passed. If you notice other effects not listed above, contact your doctor or pharmacist.


Tell your doctor if you have: kidney problems, heart disease, liver disease, Addison's disease, high blood pressure, allergies (especially drug allergies), a sodium (salt) restricted diet or use a salt substitute. This medication should be used only if clearly needed during pregnancy. Discuss the risks and benefits with your doctor. Since small amounts of this medication are found in breast milk, consult your doctor before breast-feeding.

Drug Interactions

Tell your doctor of any over-the-counter or prescription medication you may take, including: aspirin, water pills, potassium supplements, salt substitutes, antacids, steroids or medication for high blood pressure. Avoid antacids when using this medication because they may prevent its absorption. If necessary, space dosing of the medication and the antacid as far apart as possible. 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.


Laboratory tests may be done periodically while taking this medication to monitor its effectiveness and prevent side effects.

Missed Dose

If you miss a dose, take it as soon as remembered; do not take it if it is near the time for the next dose, instead, skip the missed dose and resume your usual dosing schedule. Do not "double-up" the dose to catch up.


Store at room temperature between 59 and 86 degrees F (15 to 30 degrees C) away from heat, light and moisture. Do not store in the bathroom.