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10 facts you need to know about KUVAN

In 2007, KUVAN® (sapropterin dihydrochloride) Tablets or Powder for Oral Solution was approved as the first prescription medication for PKU

KUVAN is available in 50 countries around the world1

Since FDA approval, more than 6,870 patients in the United States have been treated with KUVAN, together with a low-Phe diet*1

More than 3,100 people in the United States are currently on KUVAN*1

The safety of KUVAN has been tested in clinical studies in more than 600 people, ranging in age from 1 month to 50 years. The most common side effects reported when using KUVAN are headache, runny nose and nasal congestion, sore throat, diarrhea, vomiting, and cough2

Nearly 550 children under 4 years of age in the United States have been treated with KUVAN, together with a low-Phe diet1

PKU experts say that everyone with PKU should be offered a trial of KUVAN to see if they are a responder†3

BioMarin RareConnections™ has hosted more than 5000 events to provide disease education and information about KUVAN to people with PKU and their loved ones1

KUVAN is offered in 3 dosage forms: 100 mg Tablets, 100 mg Powder Packets, and 500 mg Powder Packets, which offer the convenience of fewer packets to open2

According to PKU experts, it’s never too late to return to treatment including diet and medication. Many people will likely see an improvement in symptoms3-6

To date, BioMarin RareConnections™ has helped approximately 7,000 people with PKU1

For support getting started or continuing on KUVAN, contact BioMarin RareConnections at

*As of December 31, 2017.
Except those with two null mutations in trans.


  1. Data on file. Novato, CA: BioMarin Pharmaceutical Inc; 2017.
  2. KUVAN [package insert]. Novato, CA: BioMarin Pharmaceutical Inc; 2016.
  3. Vockley J, Andersson HC, Antshel KM, et al. Phenylalanine hydroxylase deficiency: diagnosis and management guideline. Genet Med. 2014;16(2):188-200.
  4. Christ SE, Moffitt AJ, Peck D, White DA. The effects of tetrahydrobiopterin (BH4) treatment on brain function in individuals with phenylketonuria. Neuroimage Clin. 2013;3:539-547.
  5. Bik-Multanowski M, Didycz B, Mozrzymas R, et al. Quality of life in noncompliant adults with phenylketonuria after resumption of the diet. JIMD Short Report. 2008;133. doi:10.1007/s10545-008-0978-7.
  6. Waisbren SE, Levy HL. Agoraphobia in phenylketonuria. J Inherit Metab Dis. 1991;14(5):755-764.


KUVAN® (sapropterin dihydrochloride) Tablets for Oral Use and Powder for Oral Solution are approved to reduce blood Phe levels in people with a certain type of Phenylketonuria (PKU). KUVAN is to be used with a Phe-restricted diet.

Important Safety Information

It is not possible to know if KUVAN will work for you without a trial of the medicine. Your doctor will check your blood Phe levels when you start taking KUVAN to see if the medicine is working.

Starting KUVAN does not eliminate the need for ongoing dietary management. Any change to your diet may impact your blood Phe level. Follow your doctor’s instructions carefully. Your doctor and dietitian will continue to monitor your diet and blood Phe levels throughout your treatment with KUVAN to make sure your blood Phe levels are not too high or too low. If you have a fever, or if you are sick, your Phe level may go up. Tell your doctor and dietitian as soon as possible so they can make any necessary changes to your treatment.

Children younger than 7 years old treated with KUVAN doses of 20 mg/kg per day are at an increased risk for low levels of blood Phe compared with children 7 years and older. Frequent blood monitoring is recommended in this population to ensure that blood Phe levels do not fall too low.

Tell your doctor if you have ever had liver or kidney problems, have poor nutrition or have a loss of appetite, are pregnant or plan to become pregnant, or are breastfeeding or plan to breastfeed.

KUVAN is a prescription medicine and should not be taken by people who are allergic to any of its ingredients. KUVAN and other medicines may interact with each other. Tell your doctor about all the medicines you take, including prescription and over-the-counter medicines, vitamins, herbal and dietary supplements.

If you forget to take your dose of KUVAN, take it as soon as you remember that day. Do not take 2 doses in a day. If you take too much KUVAN, call your doctor for advice.

The most common side effects reported when using KUVAN are headache, runny nose and nasal congestion, sore throat, diarrhea, vomiting, and cough. Additional adverse reactions reported in connection with worldwide marketing include sore throat, heartburn or pain in the esophagus, inflammation of the lining of the stomach, indigestion, stomach pain, nausea, and nose irritation. These are not all the possible side effects seen with KUVAN. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

KUVAN can cause serious side effects, including:

  • Severe allergic reactions. Stop taking KUVAN and get medical help right away if you develop any of these symptoms of a severe allergic reaction:
    • Wheezing or trouble breathing
    • Nausea
    • Flushing
    • Lightheadedness or fainting
    • Coughing
    • Rash
  • Inflammation of the lining of the stomach (gastritis). Gastritis can happen with KUVAN and may be severe. Call your doctor right away if you have any:
    • Severe upper stomach-area discomfort or pain
    • Blood in your vomit or stool
    • Nausea and vomiting
    • Black, tarry stools
  • Too much or constant activity (hyperactivity) can happen with KUVAN. Tell your doctor if you have any signs of hyperactivity, including fidgeting, moving around or talking too much.

For more information, call BioMarin RareConnections™ at 1-877-MY-KUVAN (1-877-695-8826).

Please read the full Patient Information by clicking here.