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Generic name: Sodium Benzoate and Sodium Phenylacetate (systemic)
Drug class: Miscellaneous uncategorized agents

Medically reviewed by Last updated on Apr 1, 2024.

Some commonly used brand names are:

In the U.S.


What is Ammonul?

Ammonul 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:

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 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? 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 while breast-feeding. Mothers who are taking Ammonul and who wish to breast-feed should 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 problems than it does in adults.

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 Ammonul 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 Ammonul, it is especially important that your health care professional know if you are taking the following:

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

Proper Use of Ammonul

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. Your doctor will administer your dose. The following information includes only the average dose of this combination medicine.

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

Storage - To store Ammonul:

Precautions While Using Ammonul

Your doctor should check your progress at regular visits to make sure that this medicine 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 may need 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; irregular heartbeat; loss of appetite; mood changes; muscle pain or cramps; nausea; numbness or tingling in hands, feet, or lips; problems with movement, walking or speech; 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; difficulty in breathing; drowsiness; loss of consciousness; mental changes; muscle cramps in hands, arms, feet, legs, or face; muscle tremors; persistent bleeding or 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 ; 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; 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 sitting position 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; not alert; numbness to feet, hands and around mouth; rapid, shallow breathing; restlessness; seizures; slow heart rate; stiff neck; sweating; swelling of face; swelling of feet or lower legs; thickening of bronchial secretions; trouble with coordination; unusual tiredness or weakness; vomiting; weakness; yellow eyes or skin

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

Changes in skin color; cold hands and feet; confusion or excitement; cough or hoarseness;; dry mouth;; fever or chills; flushed, dry skin;; fruit-like breath odor; increased hunger; increased thirst; increased urination; lower back or side pain; mental depression or anxiety; nightmares or 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; troubled breathing with exertion; trouble sleeping; unusual bleeding or bruising

Frequency unknown

Blister; full or bloated feeling or pressure 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. If you 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.