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. 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.

RAVICTI® (glycerol phenylbutyrate) is approved for babies 2 months and older. Babies younger than 2 months should not take RAVICTI because they may not be able to digest it.

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. 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 take-by-mouth liquid medicine that’s FDA-approved to treat most types of UCDs for 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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RAVICTI is a prescription medicine for long-term treatment for people with UCDs who are at least 2 months of age and cannot manage their UCD with diet and supplements alone. RAVICTI must be used with a low-protein diet. RAVICTI is not used to treat extremely high levels of ammonia in the blood (hyperammonemic crisis) or for N-acetylglutamate synthase (NAGS) deficiency.

Important Safety Information And Approved Uses For RAVICTI® (glycerol phenylbutyrate) Oral Liquid
Who Should Not Take RAVICTI: Children... Children younger than 2 months should not take RAVICTI because they may not be able to digest it. Do not take RAVICTI if you are allergic to phenylbutyrate. Call your doctor or go to the nearest...

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Important Safety Information And Approved Uses For RAVICTI® (Glycerol Phenylbutyrate) Oral Liquid

Who Should Not Take RAVICTI:

Children younger than 2 months should not take RAVICTI because they may not be able to digest it.

Do not take RAVICTI if you are allergic to phenylbutyrate. Call your doctor or go to the nearest hospital emergency room if you have symptoms of an allergic reaction, such as wheezing, shortness of breath, cough, low blood pressure, flushing, nausea, or rash while taking RAVICTI.

RAVICTI May Cause Serious Side Effects:

The breakdown of RAVICTI produces the byproduct phenylacetate, 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, tiredness; nausea; or vomiting.

What Are The Possible Side Effects Of RAVICTI?

The most common side effects of RAVICTI in adults include diarrhea, gas, headache, nausea, vomiting, tiredness, decreased appetite, and dizziness.

The most common side effects of RAVICTI in children ages 2 to 17 years include stomach pain, nausea, vomiting, diarrhea, decreased appetite, and headache.

The most common side effects of RAVICTI in children ages 2 months to younger than 2 years include decreased level of a type of white blood cell, vomiting, diarrhea, fever, decreased appetite, cough, nasal congestion, runny nose, and rash.

Tell your doctor if you have any side effect that bothers you or that does not go away. These are not all of the possible side effects of RAVICTI. Call your doctor for medical advice about side effects.

Before You Take RAVICTI:

Tell your doctor if you have liver or kidney problems, pancreas or bowel (intestine) problems, or any other medical conditions. Tell your doctor if you are pregnant or plan to become pregnant. It is not known if RAVICTI will harm your unborn baby. Tell your doctor if you 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.

Approved Uses and Important Safety Information for RAVICTI® (glycerol phenylbutyrate) Oral Liquid

RAVICTI is a prescription medicine for people with UCDs who are at least 2 months of age and cannot manage their UCD with diet and supplements alone. RAVICTI must be used with a low-protein diet. RAVICTI is not used to treat extremely high levels of ammonia in the blood (hyperammonemic crisis) or for NAGS deficiency.

Indication for RAVICTI Oral Liquid

RAVICTI® (GLYCEROL PHENYLBUTYRATE) ORAL LIQUID INDICATIONS AND USAGE

APPROVED USES FOR RAVICTI® (GLYCEROL PHENYLBUTYRATE) ORAL LIQUID

RAVICTI is a prescription medicine used in adults and children 2 months of age and older for long-term management of high levels of ammonia in the blood (hyperammonemia) caused by a condition called a urea cycle disorder (UCD). RAVICTI must be used along with a low-protein diet and, in some cases, dietary supplements. RAVICTI should only be used if the UCD cannot be managed with a low-protein diet and dietary supplements alone.

Limitations 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 rapidly acting medication.

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

It is not known if RAVICTI is safe and effective for children younger than 2 months.

Talk to your doctor about participating in a UCD registry. The purpose of this registry is to collect information about people with UCDs to improve care. For more information about the registry program, call 1-855-823-2595 or visit www.ucdregistry.com.

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

This information is not comprehensive. To learn more, talk to your healthcare provider or pharmacist. The FDA-approved product labeling, including the Medication Guide, can be found at RAVICTI.com.

Important Safety Information And Approved Uses For RAVICTI® (Glycerol Phenylbutyrate) Oral Liquid

Who Should Not Take RAVICTI:

Children younger than 2 months should not take RAVICTI because they may not be able to digest it.

Do not take RAVICTI if you are allergic to phenylbutyrate. Call your doctor or go to the nearest hospital emergency room if you have symptoms of an allergic reaction, such as wheezing, shortness of breath, cough, low blood pressure, flushing, nausea, or rash while taking RAVICTI.

RAVICTI May Cause Serious Side Effects:

The breakdown of RAVICTI produces the byproduct phenylacetate, 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, tiredness; nausea; or vomiting.

What Are The Possible Side Effects Of RAVICTI?

The most common side effects of RAVICTI in adults include diarrhea, gas, headache, nausea, vomiting, tiredness, decreased appetite, and dizziness.

The most common side effects of RAVICTI in children ages 2 to 17 years include stomach pain, nausea, vomiting, diarrhea, decreased appetite, and headache.

The most common side effects of RAVICTI in children ages 2 months to younger than 2 years include decreased level of a type of white blood cell, vomiting, diarrhea, fever, decreased appetite, cough, nasal congestion, runny nose, and rash.

Tell your doctor if you have any side effect that bothers you or that does not go away. These are not all of the possible side effects of RAVICTI. Call your doctor for medical advice about side effects.

Before You Take RAVICTI:

Tell your doctor if you have liver or kidney problems, pancreas or bowel (intestine) problems, or any other medical conditions. Tell your doctor if you are pregnant or plan to become pregnant. It is not known if RAVICTI will harm your unborn baby. Tell your doctor if you 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.

Approved Uses and Important Safety Information for RAVICTI® (glycerol phenylbutyrate) Oral Liquid

RAVICTI is a prescription medicine for people with UCDs who are at least 2 months of age and cannot manage their UCD with diet and supplements alone. RAVICTI must be used with a low-protein diet. RAVICTI is not used to treat extremely high levels of ammonia in the blood (hyperammonemic crisis) or for NAGS deficiency.

Indication for RAVICTI Oral Liquid

RAVICTI® (GLYCEROL PHENYLBUTYRATE) ORAL LIQUID INDICATIONS AND USAGE

APPROVED USES FOR RAVICTI® (GLYCEROL PHENYLBUTYRATE) ORAL LIQUID

RAVICTI is a prescription medicine used in adults and children 2 months of age and older for long-term management of high levels of ammonia in the blood (hyperammonemia) caused by a condition called a urea cycle disorder (UCD). RAVICTI must be used along with a low-protein diet and, in some cases, dietary supplements. RAVICTI should only be used if the UCD cannot be managed with a low-protein diet and dietary supplements alone.

Limitations 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 rapidly acting medication.

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

It is not known if RAVICTI is safe and effective for children younger than 2 months.

Talk to your doctor about participating in a UCD registry. The purpose of this registry is to collect information about people with UCDs to improve care. For more information about the registry program, call 1-855-823-2595 or visit www.ucdregistry.com.

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

This information is not comprehensive. To learn more, talk to your healthcare provider or pharmacist. The FDA-approved product labeling, including the Medication Guide, can be found at RAVICTI.com.