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Generic Name: Sodium Benzoate and Sodium Phenylacetate (Systemic)

Some commonly used brand names are:

In the U.S.

  • Ammonul
  • Antihyperammonemic

Medically reviewed by Last updated on Apr 5, 2021.

What is Ammonul?

Ammonul (sodium benzoate and sodium phenylacetate combination) is used to treat a condition caused by too much ammonia in the blood (hyperammonemia). Ammonul 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 build up may cause serious unwanted effects.

Ammonul may cause nausea and vomiting. An anti-nausea medicine may be used during administration.

Ammonul is available only with your doctor's prescription in the following dosage form:

  • Injection (U.S.)

Before Using Ammonul

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 Ammonul, the following should be considered:

Allergies? Tell your doctor if you have ever had any unusual orallergic reaction to sodium benzoate or sodium phenylacetate. Also tell yourhealth care professional if you are allergic to any other substances, suchas foods, preservatives, or dyes.

Pregnancy? Ammonul has not been studied in pregnant women or animals.

Breast-feeding? It is not known whether Ammonul passes into the breast milk. Although most medicines pass into breast milk in small amounts, many of them may be used safely whilebreast-feeding. Mothers who are taking Ammonul and who wish to breast-feedshould discuss this with their doctor.

Children? Ammonul has been tested in children and, ineffective doses, has not been shown to cause different side effects or problemsthan it does in adults.

Older adults? Many medicines have not been studied specificallyin older people. Therefore, it may not be known whether they work exactlythe same way they do in younger adults or if they cause different side effectsor problems in older people. There is no specific information comparing the use of Ammonul in the elderly with use inother age groups.

Other medicines? Although certain medicines should not be usedtogether at all, in other cases two different medicines may be used togethereven 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 Ammonul, it is especially important that your health care professional know if you are taking the following:

  • Corticosteroids - May cause breakdown of body protein and increaseammonia levels in your body
  • Penicillins - Use with penicillins may keep the Ammonul from working properly

Other medical problems? The presence of other medicalproblems may affect the use of Ammonul.Make sure you tell your doctor if you have any other medical problems, especially:

  • Cancer - Use of Ammonul may increase your chance of side effects
  • Edema (swelling) or
  • Heart disease - Increased retention of water may make these conditionsworse
  • Kidney disease or
  • Liver disease - May increase the amount of medicine in your body

Proper Use of Ammonul

It is importantthat you follow any special instructions from your doctor, such as followinga low protein diet. If you have any questions about this, check with yourdoctor.

Dosing - The dose of this combination medicine willbe different for different patients. Your doctor willadminister your dose. The following information includes only the average dose of this combination medicine.

  • For injection dosage form (solution):
    • Treatment of too much ammonia in the blood:
      • Adults and children - The dose is based on body weight and mustbe determined by the doctor.

Missed dose - If you miss a dose of Ammonul, discuss withyour doctor when you should receive your next dose. Do not double doses. Ifyou have any questions about this, check with your doctor.

Storage - To store Ammonul:

  • Keep out of the reach of children.
  • Store away from heat and direct light.
  • Keep the medicine from freezing. Do not refrigerate.
  • Do not keep outdated medicine or medicine no longer needed. Be surethat any discarded medicine is out of the reach of children.

Precautions While Using Ammonul

Yourdoctor should check your progress at regular visits to make sure that thismedicine is working properly.

Ammonul 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 mayneed medical attention.

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

    More common

      Confusion; convulsions; decreased urine; dry mouth; headache; increase in frequency of seizures; increased thirst; irregularheartbeat; loss of appetite; mood changes; muscle pain or cramps; nausea; numbness or tingling in hands,feet, or lips; problems with movement, walking orspeech; shortness of breath; swelling of face; unusual tiredness or weakness; vomiting; yellow eyes or skin

    Less common

      Blood in stools; blood in urine; bruising; change in consciousness; coughing or vomiting blood; difficultyin breathing; drowsiness; loss of consciousness; mental changes; muscle cramps in hands, arms, feet, legs, or face; muscle tremors; persistent bleedingor oozing from puncture sites, mouth, or nose; rapid,deep breathing; rash; restlessness; shortness of breath; stomach cramps; tightness in chest; tremor; troubled breathing; wheezing

    Frequency unknown

      Abnormally slow deep breathing ; bluelips, fingernails, or skin; blurred vision; bulging soft spot on head of an infant; change in ability to see colors, especially blue or yellow; chest pain or discomfort; dizziness or fainting; injection site hemorrhage; insomnia; irregular, fast or slow, or shallow breathing; lightheadedness; severe headache; shakiness; sleepiness; slow heartbeat; slow to respond; slurred speech; unconsciousness

    Symptoms of overdose

      Agitation; back pain; blue lips, fingernails, or skin; blurred vision; bulging soft spot on head of an infant; change in ability to see colors, especially blue or yellow; chest pain or discomfort; chills ; cold, clammy, pale skin; coma; confusion; continuing nausea or vomiting; cough; deep or fast breathing with dizziness; difficult or troubled breathing; dizziness, faintness, or lightheadedness when getting up from a lying or sittingposition suddenly; drowsiness; fainting; fast heartbeat; fever; general feeling of discomfort or illness; hallucinations; headache; high blood pressure; insomnia; irregular, fast or slow, or shallow breathing; irregular heartbeats; irritability; lightheadedness; loss of appetite; mood or mental changes; muscle twitching; no blood pressure; notalert; numbness to feet, hands and around mouth; rapid, shallow breathing; restlessness; seizures; slow heart rate; stiff neck; sweating; swelling of face; swelling of feet orlower legs; thickening of bronchial secretions; trouble with coordination; unusual tirednessor weakness; vomiting; weakness; yellow eyes or skin

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

    More common

      Changes in skin color; cold hands andfeet; confusion or excitement; cough or hoarseness;; dry mouth;; fever or chills; flushed, dry skin;; fruit-like breath odor; increased hunger; increased thirst; increasedurination; lower back or side pain; mental depression or anxiety; nightmaresor unusually vivid dreams; painful or difficult urination; pain, redness, or swelling in arm or leg; skin disorders; sweating; unexplained weight loss

    Less common

      Bladder pain; bleeding, blistering,burning, coldness, discoloration of skin, feeling of pressure, hives, infection;inflammation, itching, lumps, numbness, pain, rash, redness, scarring, soreness,stinging, swelling, tenderness, tingling, ulceration, or warmth at site; decrease in urine-concentrating ability; diarrhea; difficult, burning, or painful urination; frequent urge to urinate; hyperventilation; nervousness; pale skin; shaking; troubledbreathing with exertion; trouble sleeping; unusual bleeding or bruising

    Frequency unknown

      Blister; full or bloated feeling orpressure in the stomach; itching skin; rash with flat lesions or small raised lesions on the skin; swelling of abdominal or stomach area; uncontrolled jerking movement

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

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.