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Generic Name: potassium acid phosphate

It is used to treat high pH levels in the urine
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What is this medicine?

PHOSPHORUS SALTS (FOS fer uhs sawlts) is used to treat high pH levels in the urine. It is used to prevent calcium kidney stones. This medicine can also work with some antibiotics for urinary tract infections.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • high levels of calcium in the blood
  • high levels of phosphate in the blood
  • kidney disease
  • phosphate stones
  • an unusual or allergic reaction to phosphorus salts, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth. Follow the directions on the package or prescription label. Dissolve this medicine in 6 to 8 ounces of water as directed. Allow tablets to soak in water for 2 to 5 minutes or more. If part of the tablet does not dissolve, it may be crushed and then the solution stirred vigorously. Shake or stir well before taking. Take your medicine at regular intervals. Do not take your medicine more often than directed.

Talk to your pediatrician regarding the use of this medicine in children. Special care may be needed.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

Do not take this medicine with any of the following medications:
  • sevelamer

This medicine may also interact with the following medications:

  • antacids containing aluminum, magnesium, or calcium
  • aspirin and aspirin-like medicines
  • cyclosporine
  • diuretics
  • eplerenone
  • medicines for blood pressure like captopril, enalapril, lisinopril
  • potassium supplements, salt substitutes, or low-salt milk
  • vitamin D supplements

What should I watch for while using this medicine?

Visit your health care professional for regular checks on your progress. Your doctor may order blood work while you are taking this medicine.

You may pass a kidney stone after starting this medicine. Contact your doctor if you have new or unusual symptoms.

Avoid products with aluminum, calcium, magnesium as these may bind to this medicine.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • bone or joint pain
  • breathing problems
  • confusion
  • fast, irregular heartbeat
  • feeling faint or lightheaded, falls
  • heaviness in the legs
  • high blood pressure
  • muscle cramps
  • tingling, pain, or numbness in the hands or feet
  • unusually weak or tired

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • diarrhea
  • nausea, vomiting
  • stomach pain

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature between 20 and 25 degrees C (68 and 77 degrees F). Protect from light. Throw away any unused medicine after the expiration date.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

All visitors to AARP.org should seek expert medical care and consult their own physicians for any specific health issues. Read this disclaimer in its entirety.
Note: This information is not intended to cover all possible uses, precautions, interactions, or adverse effects for this drug. If you have question about the drug(s) you are taking, check with your health care professional.
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