Phosphate supplement (By mouth)

Increases the amount of phosphate and acid in urine.

Brand Name(s):

Av-Phos 250 Neutral, K-Phos Neutral, K-Phos No. 2, K-Phos Original, Phospha 250 Neutral, Phospho-Trin 250 Neutral, Virt-Phos 250 Neutral

There may be other brand names for this medicine.

When This Medicine Should Not Be Used:

This medicine is not right for everyone. Do not use if you had an allergic reaction to sodium phosphate or potassium phosphate, or if you have severe kidney problems.

How to Use This Medicine:

Tablet, Liquid, Coated Tablet

  • Your doctor will tell you how much medicine to use. Do not use more than directed.
  • Place the tablets in about 8 ounces of water and let them dissolve for 2 to 5 minutes. If the tablets have not dissolved completely after 5 minutes, you may stir and break the pieces so they dissolve. Stir, and drink all the water and dissolved medicine.
  • Take this medicine at meal times and again at bedtime, unless your doctor tells you differently.
  • Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

  • Some medicines and foods can affect how this potassium supplement works. Tell your doctor if you are also using
    • Digoxin
    • Blood pressure medicine (such as guanethidine, hydralazine)
    • Steroid medicine (such as hydrocortisone, methylprednisolone, prednisone)
    • Diuretic (water pill)
    • Salicylate medicine, such as aspirin
  • Do not take an antacid that contains aluminum, calcium, or magnesium while you are using this phosphate supplement. The antacid will keep the phosphate supplements from working correctly.

Warnings While Using This Medicine:

  • Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, heart problems, high blood pressure, Addison disease, or myotonia congenita.
  • You might pass kidney stones when you first start using this medicine, if you have kidney stones already.
  • Your doctor will check your progress and the effects of this medicine at regular visits. Keep all appointments.
  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
  • Fast or uneven heartbeat

If you notice these less serious side effects, talk with your doctor:

  • Bone or joint pain
  • Diarrhea, nausea, vomiting, or stomach pain
  • Muscle cramps

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 11/6/2020

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