What Is Hyperammonemia?

When there is too much ammonia in the blood, it's called hyperammonemia (hi-per-am-oh-NEE-me-uh). Signs and symptoms of hyperammonemia may include:

  • Confusion
  • Headache
  • Dizziness
  • Seizures
  • Vomiting
  • Feeling more tired than usual
  • Not being hungry
  • Avoiding protein
  • Growth problems
  • Behavior changes
  • Coma

Any of these signs and symptoms could mean that you need to lower the amount of ammonia in your blood. If you or your loved one have any of these signs and symptoms, you may be at risk for a hyperammonemic crisis. A hyperammonemic crisis is when there are extremely high levels of ammonia in the blood. This is a serious condition that may lead to coma or death.

Hyperammonemia symptoms in babies

Signs of hyperammonemia in babies may be different. A baby with a urea cycle disorder (UCD) may be irritable at first, or refuse feedings. This may be followed by vomiting and increasing sleepiness. If left untreated, the baby may have seizures, floppiness, and breathing problems.

There are several ways to help control your or your child's ammonia levels. It's important to get a UCD diagnosis from your doctor, because there are many other health conditions that have similar symptoms to UCDs.

What can trigger a hyperammonemic crisis?

There are several things that can cause a hyperammonemic crisis, which occurs when there are extremely high levels of ammonia in the blood. Viral infections are the most common cause. Other triggers are physical or life stress, dehydration, trauma, the menstrual cycle, or changes in diet. It is important to start the appropriate treatment because hyperammonemia can continue and get worse very quickly.

If you believe you or your loved one is suffering from these symptoms listed above, or a hyperammonemic crisis, you should head to the emergency room immediately.

Even if you've never had a hyperammonemic crisis, it doesn't mean you are safe from the effects of having too much ammonia in your blood. Ammonia levels can go up and down throughout the day. If they stay high over time, long-term damage to the body or brain is possible. Once your doctor has diagnosed you with a urea cycle disorder, he or she will discuss your treatment plan. To manage your condition, it’s important to have your ammonia levels tested and to have regular check-ins with your doctor.

Important Limitation of Use:

RAVICTI is not used to treat extremely high levels of ammonia in the blood (hyperammonemic crises) in people with UCDs as they may require more rapidly acting treatment.

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About RAVICTI

A liquid medicine that can be taken by mouth that's FDA-approved to treat most types of UCDs for newborns, babies, children, and adults. See approved uses below.

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Lauren, UCD patient
Lauren, UCD patient

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"I chose RAVICTI… it's easy for me to take." – Lauren | Patient

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APPROVED USES and IMPORTANT SAFETY INFORMATION for RAVICTI
What is the most important safety information I should know about RAVICTI?
RAVICTI may cause serious side effects, including: Nervous system side effects (Neurotoxicity).
 The breakdown of RAVICTI produces the byproduct phenylacetate (PAA), which may cause nervous system side effects.

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What is RAVICTI?

RAVICTI (glycerol phenylbutyrate) Oral Liquid is a prescription medicine used for long-term management of high blood levels of ammonia (hyperammonemia) caused by a condition called a urea cycle disorder (UCD). RAVICTI should be used if the UCD cannot be managed with a low-protein diet and dietary supplements alone. RAVICTI must be used along with a low-protein diet and in some cases, dietary supplements.

RAVICTI is not used to treat extremely high levels of ammonia in the blood (hyperammonemic crisis) in people with UCDs.

It is not known if RAVICTI is safe and effective for the treatment ofN-acetylglutamate synthase (NAGS) deficiency.

IMPORTANT SAFETY INFORMATION

What is the most important safety information I should know about RAVICTI?

RAVICTI may cause serious side effects, including:

Nervous system side effects (Neurotoxicity). The breakdown of RAVICTI produces the byproduct phenylacetate (PAA), which may cause nervous system side effects.

Call your doctor or get medical help right away if you have any of these symptoms while taking RAVICTI:

  • sleepiness
  • lightheadedness
  • change in taste
  • problems with hearing
  • confusion
  • problems with memory
  • worsening of numbness, tingling, or burning in your hands or feet
  • headache
  • feeling very tired (fatigue)
  • nausea
  • vomiting

Who should not take RAVICTI?

Do not take RAVICTI if you are allergic to phenylbutyrate. Call your doctor or go to the nearest hospital emergency room if you experience any of the following symptoms of an allergic reaction while taking RAVICTI:

  • wheezing
  • shortness of breath
  • cough
  • low blood pressure
  • flushing
  • nausea
  • skin rash

What should I tell my doctor before taking RAVICTI?

Tell your doctor about any medical conditions and if you:

  • Have liver or kidney problems.
  • Have pancreas or bowel (intestine) problems.
  • Are pregnant or plan to become pregnant. It is not known if RAVICTI will harm your unborn baby.
    • Pregnancy Registry: There is a Pregnancy Registry for women who take RAVICTI just before becoming pregnant or who become pregnant during treatment with RAVICTI. The purpose of this registry is to collect information about the health of you and your baby. Talk to your doctor about how you can join the Pregnancy Registry. For more information about this registry, call 1-855-823-2595 or visit www.ucdregistry.com.
  • Are breastfeeding or plan to breastfeed. It is not known if RAVICTI passes into your breast milk. Breastfeeding is not recommended during treatment with RAVICTI. Talk to your doctor about the best way to feed your baby if you take RAVICTI.

What are possible side effects of RAVICTI?

RAVICTI may cause serious side effects, including:

  • See "What is the most important information I should know about RAVICTI?"

The most common side effects of RAVICTI in adults include:

  • diarrhea
  • gas
  • headache
  • abdomen (stomach) pain
  • vomiting
  • tiredness
  • decreased appetite
  • indigestion or heartburn

The most common side effects of RAVICTI in children 2 years to 17 years of age include:

  • upper abdomen (stomach) pain
  • rash
  • nausea
  • vomiting
  • diarrhea
  • decreased appetite
  • headache

The most common side effects of RAVICTI in children 2 months to less than 2 years of age include:

  • low white blood cell count (neutropenia)
  • vomiting
  • diarrhea
  • fever
  • reduced food intake
  • cough
  • stuffy nose
  • runny nose
  • skin rash
  • small round bumps on the skin

The most common side effects of RAVICTI in children less than 2 months of age include:

  • vomiting
  • rash
  • gastroesophageal reflux
  • increased levels of liver enzymes in the blood
  • decreased appetite and reduced food intake
  • low red blood cell count (anemia)
  • cough
  • loss of too much body fluid (dehydration)
  • too much acid in the blood (acidosis)
  • high blood platelet count (thrombocytosis)
  • low blood platelet count (thrombocytopenia)
  • low blood neutrophil count (type of white blood cell) (neutropenia)
  • high white blood cell count (lymphocytosis)
  • diarrhea
  • gas
  • constipation
  • fever
  • drowsiness (lethargy)
  • irritability
  • agitation

These are not all of the possible side effects of RAVICTI. Call your doctor for medical advice about side effects.

For additional important safety information, click here for the Full Prescribing Information and Medication Guide and discuss with your doctor.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit http://www.fda.gov/medwatch or call 1-800-FDA-1088.

What is RAVICTI?

RAVICTI (glycerol phenylbutyrate) Oral Liquid is a prescription medicine used for long-term management of high blood levels of ammonia (hyperammonemia) caused by a condition called a urea cycle disorder (UCD). RAVICTI should be used if the UCD cannot be managed with a low-protein diet and dietary supplements alone. RAVICTI must be used along with a low-protein diet and in some cases, dietary supplements.

RAVICTI is not used to treat extremely high levels of ammonia in the blood (hyperammonemic crisis) in people with UCDs.

It is not known if RAVICTI is safe and effective for the treatment ofN-acetylglutamate synthase (NAGS) deficiency.

IMPORTANT SAFETY INFORMATION

What is the most important safety information I should know about RAVICTI?

RAVICTI may cause serious side effects, including:

Nervous system side effects (Neurotoxicity). The breakdown of RAVICTI produces the byproduct phenylacetate (PAA), which may cause nervous system side effects.

Call your doctor or get medical help right away if you have any of these symptoms while taking RAVICTI:

  • sleepiness
  • lightheadedness
  • change in taste
  • problems with hearing
  • confusion
  • problems with memory
  • worsening of numbness, tingling, or burning in your hands or feet
  • headache
  • feeling very tired (fatigue)
  • nausea
  • vomiting

Who should not take RAVICTI?

Do not take RAVICTI if you are allergic to phenylbutyrate. Call your doctor or go to the nearest hospital emergency room if you experience any of the following symptoms of an allergic reaction while taking RAVICTI:

  • wheezing
  • shortness of breath
  • cough
  • low blood pressure
  • flushing
  • nausea
  • skin rash

What should I tell my doctor before taking RAVICTI?

Tell your doctor about any medical conditions and if you:

  • Have liver or kidney problems.
  • Have pancreas or bowel (intestine) problems.
  • Are pregnant or plan to become pregnant. It is not known if RAVICTI will harm your unborn baby.
    • Pregnancy Registry: There is a Pregnancy Registry for women who take RAVICTI just before becoming pregnant or who become pregnant during treatment with RAVICTI. The purpose of this registry is to collect information about the health of you and your baby. Talk to your doctor about how you can join the Pregnancy Registry. For more information about this registry, call 1-855-823-2595 or visit www.ucdregistry.com.
  • Are breastfeeding or plan to breastfeed. It is not known if RAVICTI passes into your breast milk. Breastfeeding is not recommended during treatment with RAVICTI. Talk to your doctor about the best way to feed your baby if you take RAVICTI.

What are possible side effects of RAVICTI?

RAVICTI may cause serious side effects, including:

  • See "What is the most important information I should know about RAVICTI?"

The most common side effects of RAVICTI in adults include:

  • diarrhea
  • gas
  • headache
  • abdomen (stomach) pain
  • vomiting
  • tiredness
  • decreased appetite
  • indigestion or heartburn

The most common side effects of RAVICTI in children 2 years to 17 years of age include:

  • upper abdomen (stomach) pain
  • rash
  • nausea
  • vomiting
  • diarrhea
  • decreased appetite
  • headache

The most common side effects of RAVICTI in children 2 months to less than 2 years of age include:

  • low white blood cell count (neutropenia)
  • vomiting
  • diarrhea
  • fever
  • reduced food intake
  • cough
  • stuffy nose
  • runny nose
  • skin rash
  • small round bumps on the skin

The most common side effects of RAVICTI in children less than 2 months of age include:

  • vomiting
  • rash
  • gastroesophageal reflux
  • increased levels of liver enzymes in the blood
  • decreased appetite and reduced food intake
  • low red blood cell count (anemia)
  • cough
  • loss of too much body fluid (dehydration)
  • too much acid in the blood (acidosis)
  • high blood platelet count (thrombocytosis)
  • low blood platelet count (thrombocytopenia)
  • low blood neutrophil count (type of white blood cell) (neutropenia)
  • high white blood cell count (lymphocytosis)
  • diarrhea
  • gas
  • constipation
  • fever
  • drowsiness (lethargy)
  • irritability
  • agitation

These are not all of the possible side effects of RAVICTI. Call your doctor for medical advice about side effects.

For additional important safety information, click here for the Full Prescribing Information and Medication Guide and discuss with your doctor.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit http://www.fda.gov/medwatch or call 1-800-FDA-1088.