Description and Brand Names

Drug information provided by: Merative, Micromedex®


Sodium phosphate dibasic and sodium phosphate monobasic combination is a laxative that is used to relieve occasional constipation in adults and children.

This medicine is available without your doctor's prescription.

This product is available in the following dosage forms:

  • Enema

Before Using

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:


Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.


Appropriate studies performed to date have not demonstrated pediatric-specific problems that would limit the usefulness of sodium phosphate dibasic and sodium phosphate monobasic combination in children. However, use of this medicine is not recommended in children younger than 2 years of age.


No information is available on the relationship of age to the effects of sodium phosphate dibasic and sodium phosphate monobasic combination in geriatric patients.

Drug Interactions

Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. Tell your healthcare professional if you are taking any other prescription or nonprescription (over-the-counter [OTC]) medicine.

Other Interactions

Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.

Other Medical Problems

The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:

  • Dehydration or
  • Kidney disease or
  • Stomach or bowel problems (including abdominal or stomach pain, nausea, vomiting, or a sudden change in bowel habits lasting for more than 2 weeks)—Use with caution. May make these conditions worse.

Proper Use

Use this medicine exactly as directed by your doctor. Do not use more of it, do not use it more often, and do not use it for a longer time than your doctor ordered. Tell your doctor if you or your child is on a sodium-restricted diet.

Follow the instructions on the medicine label if you are using this medicine without a prescription.

To use:

  • This medicine is for rectal use only. Do not swallow the medicine.
  • Wash your hands with soap and water before and after you use this medicine.
  • Lie on your left side with your left leg straight or slightly bent, and your right knee bent upward. Insert the applicator tip into your rectum about an inch. Gently squeeze the bottom of the bottle to release the enema.
  • Remove the bottle and throw it away.
  • You may need to hold the liquid in your rectum for several minutes or hours. This may be difficult or feel uncomfortable. It should become easier to do as you continue to use the medicine.
  • If your child is using one-half bottle: Unscrew cap and remove 2 tablespoons of liquid with a measuring spoon. Replace cap and follow your doctor's directions.
  • Do not use more than one bottle of enema in 24 hours. Do not use if the seal of the bottle enema is broken or missing.


The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.

The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.

  • For rectal dosage form (enema):
    • For relief of constipation:
      • Adults and children 12 years of age and older—One bottle of Fleet® saline enema.
      • Children 5 to 11 years of age—One bottle of Pedia-Lax™ enema or as directed by your doctor.
      • Children 2 to 5 years of age—One-half bottle of Pedia-Lax™ enema.
      • Children younger than 2 years of age—Use is not recommended.


Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.

Keep out of the reach of children.

Do not keep outdated medicine or medicine no longer needed.

Ask your healthcare professional how you should dispose of any medicine you do not use.


It is very important that your doctor check your progress at regular visits. This will allow your doctor to see if the medicine is working properly and to decide if you or your child should continue to use it.

Tell your doctor if you or your child had already used a laxative for more than 1 week.

Call your doctor right away if you or your child has rectal bleeding, no bowel movement within 30 minutes of enema use, or has symptoms of dehydration (eg, confusion, decreased urination, feeling thirsty, vomiting). These maybe symptoms of a serious condition.

Do not use this medicine if you or your child is using another product containing sodium phosphate.

Side Effects

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Incidence not known

  1. Bleeding in the rectum
  2. confusion
  3. decreased urination
  4. dizziness
  5. dry mouth
  6. fainting
  7. increase in heart rate
  8. lightheadedness
  9. rapid breathing
  10. sunken eyes
  11. thirst
  12. unusual tiredness or weakness
  13. wrinkled skin

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

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