In the U.S.—

• Antihyperammonemic

Sodium benzoate and sodium phenylacetate (SOE-dee-um BEN-zo-ate and SOE-dee-um fen-ill-AH-seh-tate) combination is used to treat a condition caused by too much ammonia in the blood (hyperammonemia). This medicine works by causing less ammonia to be produced by the body.

Ammonia is formed from the breakdown of protein in the body. If the ammonia cannot be removed by the body, then a buildup may cause serious unwanted effects.

Sodium benzoate and sodium phenylacetate combination is available only with your doctor's prescription in the following dosage form:

Oral
• Oral solution (U.S.)

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 sodium benzoate and sodium phenylacetate combination, the following should be considered:

Allergies—Tell your doctor if you have ever had any unusual or allergic reaction to sodium benzoate or sodium phenylacetate. Also tell your health care professional if you are allergic to any other substances, such as foods, preservatives, or dyes.

Pregnancy—Sodium benzoate and sodium phenylacetate combination has not been studied in pregnant women or animals.

Breast-feeding—It is not known whether sodium benzoate and sodium phenylacetate combination passes into the breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely while breast-feeding. Mothers who are taking this medicine and who wish to breast-feed should discuss this with their doctor.

Children—Sodium benzoate and sodium phenylacetate may cause serious unwanted effects if given to infants of low birthweight.

Older adults—Many medicines have not been studied specifically in older people. Therefore, it may not be known whether they work exactly the same way they do in younger adults or if they cause different side effects or problems in older people. There is no specific information comparing the use of sodium benzoate and sodium phenylacetate in the elderly with use in other age groups.

Other medicines—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. When you are taking sodium benzoate and sodium phenylacetate combination, it is especially important that your health care professional know if you are taking the following:

• Penicillins—Use with penicillins may keep the sodium benzoate and sodium phenylacetate combination from working properly

• Edema (swelling) or
• Heart disease or
• Kidney disease or
• Toxemia of pregnancy—Increased retention of water may make these conditions worse

This medicine should be added to infant formula or milk and given immediately after mixing. Sodium benzoate and sodium phenylacetate should not be mixed with other beverages (especially acidic beverages such as tea or coffee), since they may cause the medicine to separate out.

Take this medicine with meals.

It is important that you follow any special instructions from your doctor, such as following a low protein diet. If you have any questions about this, check with your doctor.

Dosing—

The dose of this combination 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 dose of this combination medicine. If your dose is different, do not change it unless your doctor tells you to do so.

• For oral dosage form (solution):
  • Treatment of too much ammonia in the blood:
    • Adults and children—The dose is based on body weight and must be determined by the doctor. It is usually 2.5 milliliters (mL) per kilogram (1.1 mL per pound) a day, given in three to six divided doses. The dose is usually no more than 100 mL a day.

Missed dose—

If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.

Storage—

To store this medicine:

• Keep out of the reach of children.
• Store away from heat and direct light.
• Do not store in the bathroom, near the kitchen sink, or in other damp places. Heat or moisture may cause the medicine to break down.
• Keep the medicine from freezing. Do not refrigerate.
• Do not keep outdated medicine or medicine no longer needed. Be sure that any discarded medicine is out of the reach of children.

Your doctor should check your progress at regular visits to make sure that this medicine is working properly.

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.

Stop taking this medicine and get emergency help immediately if any of the following side effects occur:

• Symptoms of overdose
  • Continual vomiting;  feeling of faintness ;  rapid fall in blood pressure;  shortness of breath or troubled breathing;  unusual drowsiness;  unusual irritability 
  
  

Other side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. However, check with your doctor if either of the following side effects continue or are bothersome:

• More common
  • Nausea or vomiting 
  
  

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