Sodium Phosphate Monobasic; Sodium Phosphate Dibasic Tablets

Sodium phosphate is a medication that cleans out your bowel. You’ll receive this medication before a colonoscopy. This procedure is a type of endoscopy that looks inside your colon with a special scope inserted through your anus. Follow the directions on the label to take these tablets as directed with a glass of water.

What is this medication?

SODIUM PHOSPHATE SALTS (SOE dee um FOS fate sawlts) cleans the bowel out before a medical procedure. It works by increasing the amount of water your intestine absorbs. This softens the stool, making it easier to have a bowel movement. It also increases pressure, which prompts the muscles in your intestines to move stool. It belongs to a group of medications called laxatives.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): OsmoPrep, Visicol


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What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Abnormal electrolytes, such as sodium, phosphate, potassium or calcium
  • Bowel problems, such as colitis, constipation, and obstruction
  • Chest pain caused by angina
  • Dehydration
  • Heart failure
  • Kidney disease
  • Seizures
  • An unusual or allergic reaction to sodium phosphate, other medications, foods, dyes, or preservatives
  • Pregnant or trying to get pregnant
  • Breast-feeding

How should I use this medication?

Take this medication by mouth with a full glass of water. Take it as directed on the prescription label at the same time every day. You must drink at least 8 ounces of clear liquids with each dose of this medication. Examples of clear liquids are water, flavored water, lemonade (no pulp), ginger ale, or apple juice. Do not eat or drink any liquids of foods colored purple or red. Do not eat or drink any foods or liquids containing pulp material. If you do not drink enough liquids while you are taking this medication you can get dehydrated, which can cause serious side effects. Do not take any other medications by mouth within 1 hour before or after starting each dose.

A special MedGuide will be given to you by the pharmacist with each prescription and refill. Be sure to read this information carefully each time.

Talk to your care team about the use of this medication in children. Special care may be needed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.


What if I miss a dose?

This does not apply. This medication is not for regular use.

What may interact with this medication?

  • Aspirin
  • Certain medications used to treat high blood pressure, such as captopril, enalapril, lisinopril, or candesartan, losartan, valsartan
  • Diuretics
  • NSAIDS, medications for pain and inflammation, such as ibuprofen or naproxen

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.


What should I watch for while using this medication?

Do not use any other bowel-cleansing preparations, like enemas, while you are taking this medication. Take only clear liquids starting at least 12 hours before starting this medication. Examples of clear liquids are water, flavored water, lemonade (no pulp), ginger ale or apple juice. Do not drink any liquids colored purple or red.

Talk to your care team if you are not able to complete the regimen as prescribed.

See your care team right away if you do not have a bowel movement after using this medication.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Fast or irregular heartbeat
  • Kidney injury—decrease in the amount of urine, swelling of the ankles, hands, or feet
  • Seizures

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

  • Bloating
  • Nausea
  • Stomach pain
  • Vomiting

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

Keep out of the reach of children and pets.

Store at room temperature between 15 and 30 degrees C (59 and 86 degrees F). Get rid of any unused medication after your procedure.

To get rid of medications that are no longer needed or have expired:

  • Take the medications to a medication take-back program. Check with your pharmacy or law enforcement to find a location.
  • If your cannot return the medication, check the label or package insert to see if the medication should be thrown out in the garbage or flushed down the toilet. If you are not sure, ask your care team. If it is safe to put it in the trash, take the medication out of the container. Mix the medication with cat litter, dirt, coffee grounds, or other unwanted substance. Seal the mixture in a bag or container. Put it in the trash.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

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Note: Introduction and Additional Common Questions written and medically approved by Cleveland Clinic professionals.

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