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Sapropterin Tablets

Generic name: Sapropterin Tablets [ sap-roe-TER-in ]
Brand name: Kuvan
Drug class: Miscellaneous metabolic agents

Medically reviewed by Last updated on Dec 30, 2022.

Uses of Sapropterin Tablets:

What do I need to tell my doctor BEFORE I take Sapropterin Tablets?

  • If you are allergic to this medicine (sapropterin tablets); any part of this medicine (sapropterin tablets); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.

This medicine may interact with other drugs or health problems.

Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this medicine (sapropterin tablets) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.

What are some things I need to know or do while I take Sapropterin Tablets?

  • Tell all of your health care providers that you take this medicine (sapropterin tablets). This includes your doctors, nurses, pharmacists, and dentists.
  • Have blood work checked as you have been told by the doctor. Talk with the doctor.
  • Talk with your doctor if you have a fever or you are sick. Your dose may need to be changed.
  • Follow the diet plan that your doctor told you about.
  • Some people have had low blood phenylalanine levels with this medicine (sapropterin tablets). The chance is raised in children younger than 7 years of age. Blood levels that are too low for a long time may lead to very bad health problems. Talk with the doctor.
  • Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.

How is this medicine (Sapropterin Tablets) best taken?

Use this medicine (sapropterin tablets) as ordered by your doctor. Read all information given to you. Follow all instructions closely.

  • Take this medicine (sapropterin tablets) at the same time of day.
  • Take with a meal.
  • This medicine may be swallowed whole or mixed in water or apple juice.
  • If mixing the tablets, mix with 1/2 to 1 cup (4 to 8 ounces/120 to 240 mL) of water or apple juice. Drink within 15 minutes of mixing. It may take a few minutes for the tablets to dissolve. You may stir or crush the tablets to help the tablets dissolve faster. Rinse glass with more juice or water and drink.
  • This medicine may not dissolve all the way. You may see small pieces floating on the top of the water or apple juice. This is normal and safe to swallow.
  • This medicine may also be crushed and mixed in a small amount of soft food like applesauce or pudding.

What do I do if I miss a dose?

  • Take a missed dose as soon as you think about it on the same day you missed the dose.
  • If you do not think about the missed dose until the next day, skip the missed dose and go back to your normal time.
  • Do not take 2 doses on the same day.

What are some side effects that I need to call my doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your doctor or get medical help right away if you have any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Dizziness.
  • Flushing.
  • Cough.
  • Shortness of breath.
  • Fidgeting, moving around too much, or talking too much.
  • Chest pain or pressure or passing out.
  • Passing urine more often.
  • Seizures.
  • Swelling in the arms or legs.
  • Feeling agitated.
  • Stomach or bowel problems have happened with this medicine (sapropterin tablets). If not treated, these can lead to severe health problems like stomach or bowel ulcers or bleeding. Call your doctor right away if you have throat or stomach pain, severe upset stomach or throwing up, trouble swallowing, or feeling less hungry. Call your doctor right away if you throw up blood; have throw up that looks like coffee grounds; or have black, tarry, or bloody stools.

What are some other side effects of Sapropterin Tablets?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:

These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.

You may report side effects to the FDA at 1-800-332-1088. You may also report side effects at

If OVERDOSE is suspected:

If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

How do I store and/or throw out Sapropterin Tablets?

  • Store at room temperature in a dry place. Do not store in a bathroom.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.
  • Store in original container.
  • Keep lid tightly closed.

Consumer Information Use and Disclaimer

  • If your symptoms or health problems do not get better or if they become worse, call your doctor.
  • Do not share your drugs with others and do not take anyone else's drugs.
  • Some drugs may have another patient information leaflet. Check with your pharmacist. If you have any questions about this medicine (sapropterin tablets), please talk with your doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Further information

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