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Sodium biphosphate and sodium phosphate

Generic name: sodium biphosphate and sodium phosphate (oral) [SOE-dee-um-bye-FOS-fate-and-SOE-dee-um-FOS-fate]

Brand name: osmoprep
Forms of dosage: oral solution (18%–48%) or oral tablet (1.5g).
Drug class: laxatives

What are Sodium biphosphate and sodium phosphate?

A combination medicine containing sodium chloride and sodium biphosphate is used to treat constipation in adults and to cleanse the bowels before undergoing a colonoscopy.

This medication guide does not list all possible uses of sodium biphosphate or sodium phosphate.

Side effects of Sodium biphosphate and sodium phosphate

If you experience any of the following symptoms of an allergic reaction, seek immediate medical attention: hives, dizziness, wheezing or difficulty breathing, swelling of the face, lips, throat, tongue, or mouth.

Side effects from sodium biphosphate or sodium phosphate can be serious. If you experience:

  • No bowel movements after taking this medication
  • Severe stomach pain, bleeding in the rectal area, or reddish bowel movements
  • Heart rate can be fast, slow, or uneven.
  • Little or no urination
  • A seizure (blackout or convulsions);
  • Headache, dizziness, and vomiting

Side effects of sodium biphosphate or sodium phosphate include:

  • Bloating;
  • Nausea, vomiting,
  • Stomach pain.

There may be other side effects. For medical advice on side effects, call your doctor. The FDA can be contacted at 1-800-FDA-1088 to report side effects.


This medicine should not be used if you suffer from kidney disease, have an obstruction of the bowel, perforated bowels, toxic megacolon or colitis, or if there is a history of gastric bypass surgery.

This medicine may cause kidney failure in rare cases. Especially if you have kidney disease, congestive heart failure, or severe constipation. You also might be at risk if your bowels are inflamed. Certain other medications can increase your risk of kidney problems.

Before you take this drug

If you are allergic or have any of the following:

  • If you have kidney disease or if a biopsy has shown that your kidneys are affected by too much phosphate, then this is the condition for you.
  • A bowel obstruction
  • A perforated bowel
  • Colitis or toxic Megacolon
  • A history of stomach stapling or gastric bypass surgery

Rarely, sodium biphosphate or sodium phosphate may cause kidney failure. This is especially true if you:

  • You have kidney disease.
  • You have congestive cardiac failure.
  • You have severe constipation or an inflammatory bowel disorder.
  • You take certain medications to treat hypertension and heart disease.
  • You take an NSAID.
  • You are older than 55 years old.
  • You are dehydrated.

Osmoprep should not be used if it has been used within the last 7 days.

If you suffer from:

  • Kidney disease
  • Heart disease
  • Dehydration, or an electrolyte balance (such as high or low levels in your blood of sodium, calcium, potassium, or phosphorous);
  • A seizure;
  • Stomach surgery
  • An intestinal disease such as ulcerative colitis or inflammatory bowel disease;
  • Trouble swallowing is a sign of gastroesophageal reflux disease (GERD).
  • Withdrawal from alcohol or drug addiction
  • If you're on a diet that is low in salt,
  • If you have used laxatives for at least 7 days,

Consult your doctor before taking this medication if you're pregnant or breastfeeding. Do not administer this medicine without first consulting with a physician.

How to take Sodium biphosphate and sodium phosphate?

Follow the instructions on the label or those prescribed by your doctor. Too much of this medication can have rare but potentially life-threatening effects on the kidneys and heart. Please carefully read and follow all directions included with your medication. If you don't understand the instructions, ask your doctor or pharmacist. Drink plenty of water before, during, and after taking the medicine to avoid dehydration. Avoid drinking milk, red or purple liquids, pulpy juices, and drinks containing alcohol.

Follow your doctor's instructions regarding the timing and dosage of your medication. If you are preparing for a colonoscopy or treating constipation, you may have to adhere to a special diet. You should follow your doctor's advice regarding any restrictions you may have on foods or drinks.Store away from moisture or heat at room temperature. After your treatment, throw away any remaining medicine.

What happens if I miss the dose?

If you miss a dosage or don't finish the prescribed doses before your colonoscopy, call your doctor to get instructions. Use the recommended dosage of sodium biphosphate or sodium phosphate within a 24-hour period.

What happens if I overdose?

Call 1-800-222-1222 for poison help or seek immediate medical attention.

What should be avoided?

Use only the laxatives and enemas recommended. You should avoid taking oral medicines within 1 hour before or after you take sodium biphosphate and potassium phosphate. Take oral medications at least 1 hour after taking sodium biphosphate or sodium phosphate.

Interaction with other drug

Before using any other medication, ask your doctor or pharmacist about the possible interactions between sodium biphosphate (or sodium phosphate) and:

  • A diuretic, or "water pill".
  • Blood pressure medication
  • Medicine to treat kidney problems;
  • Seizure medication;
  • A sedative—alprazolam, diazepam, triazolam, Valium, Xanax, and others;
  • Aspirin, Ibuprofen, Naproxen, Diclofenac, and Indomethacin are all nsaids.

This list is incomplete. This list is not complete. Other drugs, such as vitamins, herbal products, prescription and over-the-counter medicines, and prescription and OTC medications, may also affect sodium biphosphate or sodium phosphate. This list does not include all possible drug interactions.



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