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Potassium and sodium phosphates

Generic Name: potassium and sodium phosphates (poe-TAS-ee-um and SOE-dee-um FOS-fates)
Brand Name: Examples include K-Phos Neutral and Phospha 250 Neutral

Potassium and sodium phosphates is used for:

Increasing phosphate levels in the urine. It may also be used for other conditions as determined by your doctor.

Potassium and sodium phosphates is a phosphorus supplement. It works by providing phosphate to the body.

Do NOT use potassium and sodium phosphates if:

  • you are allergic to any ingredient in potassium and sodium phosphates
  • you have severe kidney problems, infected kidney stones, or impacted feces
  • you have decreased urination or are unable to urinate
  • you have high levels of phosphate or potassium in the blood

Contact your doctor or health care provider right away if any of these apply to you.

Before using potassium and sodium phosphates:

Some medical conditions may interact with potassium and sodium phosphates. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have high blood sodium levels or low blood calcium levels, or you are on a sodium-restricted or potassium-restricted diet
  • if you have a history of heart problems (eg, heart failure), high blood pressure, swelling (eg, of the hands, ankles, or feet), fluid in the lungs, kidney problems, kidney or other urinary stones, certain muscle problems (eg, myotonia congenita, rhabdomyolysis), stomach or bowel problems (eg, inflammation), liver problems, adrenal gland problems (eg, Addison disease), inflammation of the pancreas, or parathyroid problems
  • if you have preeclampsia (high blood pressure during pregnancy)
  • if you are dehydrated or have rickets, softened or weakened bones, or a urinary tract infection
  • if you have a condition in which your skin is breaking down (eg, severe burns)

Some MEDICINES MAY INTERACT with potassium and sodium phosphates. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Aldosterone blockers (eg, eplerenone), aliskiren, angiotensin-converting enzyme (ACE) inhibitors (eg, enalapril), potassium-sparing diuretics (eg, triamterene), or potassium supplements because high potassium levels, possibly with irregular heartbeat or a heart attack, may occur
  • Corticosteroids (eg, prednisone, corticotropin) or medicine for high blood pressure (eg, diazoxide, guanethidine, hydralazine, methyldopa) because the risk of high blood sodium levels may be increased
  • Digoxin because the risk of its side effects may be increased by potassium and sodium phosphates

This may not be a complete list of all interactions that may occur. Ask your health care provider if potassium and sodium phosphates may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use potassium and sodium phosphates:

Use potassium and sodium phosphates as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take potassium and sodium phosphates by mouth with meals and at bedtime, unless your doctor tells you otherwise.
  • Take potassium and sodium phosphates with a full glass (8 oz [240 mL]) of water.
  • Do not take antacids containing aluminum, magnesium, or calcium with potassium and sodium phosphates without checking with your doctor or pharmacist.
  • If you miss a dose of potassium and sodium phosphates, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use potassium and sodium phosphates.

Important safety information:

  • Potassium and sodium phosphates may cause dizziness. This effect may be worse if you take it with alcohol or certain medicines. Use potassium and sodium phosphates with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • While taking potassium and sodium phosphates, the possibility of passing old kidney stones is increased.
  • Check with your doctor before you use a salt substitute or a product that has potassium in it.
  • LAB TESTS, including kidney function and electrolyte levels (eg, calcium, potassium, phosphorus, sodium), may be performed while you use potassium and sodium phosphates. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.
  • Potassium and sodium phosphates should be used with extreme caution in CHILDREN younger than 4 years old; safety and effectiveness in these children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: It is not known if potassium and sodium phosphates can cause harm to the fetus. If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using potassium and sodium phosphates while you are pregnant. It is not known if this medicine is found in breast milk. If you are or will be breast-feeding while you use potassium and sodium phosphates, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of potassium and sodium phosphates:

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Diarrhea; nausea; stomach pain; vomiting.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bone or joint pain; confusion; decreased urination; dizziness; fast or irregular heartbeat; increased thirst; muscle cramps; numbness or tingling around the lips; numbness, tingling, pain, or weakness in the hands or feet; seizures; severe or persistent diarrhea or headache; shortness of breath; swelling of the hands, ankles, or feet; unusual tiredness; unusual weakness or heaviness of the legs; unusual weight gain.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately.

Proper storage of potassium and sodium phosphates:

Store potassium and sodium phosphates at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep potassium and sodium phosphates out of the reach of children and away from pets.

General information:

  • If you have any questions about potassium and sodium phosphates, please talk with your doctor, pharmacist, or other health care provider.
  • Potassium and sodium phosphates is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take potassium and sodium phosphates or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about potassium and sodium phosphates. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to potassium and sodium phosphates. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using potassium and sodium phosphates.

Issue Date: June 3, 2015