Kuvan

Generic Name: sapropterin (SAP roe TER in)
Brand Names: Kuvan

What is Kuvan?

Kuvan is a synthetic form of a natural salt that contributes to the function of a certain enzyme in the body. In people with a condition called phenylketonuria (PKU), this enzyme is lacking or missing in the body. Without the enzyme, phenylalanine levels can become elevated and cause a variety of neurologic symptoms.

Kuvan is used to help the body activate the enzyme needed to control blood levels of phenylalanine. Kuvan is used in people with PKU.

Kuvan may also be used for other purposes not listed here.

Important information about Kuvan

Before using Kuvan, tell your doctor if you are allergic to any drugs, or if you have liver disease, a history of stomach ulcer or bleeding, or a seizure disorder.

Also tell your doctor about any medications you use, especially levodopa (Larodopa, Altamet, Parcopa, Sinemet), methotrexate (Rheumatrex, Trexall), or any medication to treat erectile dysfunction, such as sildenafil (Viagra), tadalafil (Cialis), or vardenafil (Levitra).

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To be sure Kuvan is helping your condition, your blood will need to be tested on a regular basis. Do not miss any scheduled appointments.

Kuvan is only part of a complete program of treatment that also includes a special diet. It is very important to follow the diet plan created for you by your doctor or nutrition counselor. You should become very familiar with the list of foods you must avoid to help control your condition.

If Kuvan is not controlling your condition properly, you may have symptoms such as behavior changes, numbness or tingling, or problems with speech, vision, or balance. Call your doctor if you have any of these symptoms.

Follow your doctor's instructions about any restrictions on food, beverages, or activity while you are using Kuvan.

Before taking Kuvan

Before using Kuvan, tell your doctor if you are allergic to any drugs, or if you have:

• liver disease;

• a history of stomach ulcer or bleeding; or

• epilepsy or other seizure disorder.

If you have any of these conditions, you may not be able to take Kuvan, or you may need a dose adjustment or special tests during treatment.

FDA pregnancy category C. This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment. It is not known whether Kuvan passes into breast milk or if it could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take Kuvan?

Take Kuvan exactly as prescribed by your doctor. Do not take it in larger amounts or for longer than recommended. Follow the directions on your prescription label.

Kuvan is usually given once daily. Follow your doctor's instructions.

Kuvan works best if you take it with food.

Dissolve the tablet in 4 to 8 ounces of water or apple juice. It will take about 15 minutes for the tablet to dissolve. Stir this mixture and then drink all of it right away. To make sure you get the entire dose, add a little more water or juice to the same glass, swirl gently and drink right away.

The tablet may not completely dissolve and you may see small pieces in the liquid. These pieces are safe for you to swallow.

To be sure Kuvan is helping your condition, your blood will need to be tested on a regular basis. Do not miss any scheduled appointments.

Kuvan can reduce your phenylalanine blood levels within 24 hours of when you take it. However, it may take up to 30 days of using this medicine before it reaches its fullest effect in your body. For best results, keep using the medication as directed.

Kuvan is only part of a complete program of treatment that also includes a special diet. It is very important to follow the diet plan created for you by your doctor or nutrition counselor. You should become very familiar with the list of foods you must avoid to help control your condition.

Store Kuvan at room temperature away from moisture and heat. Keep the bottle tightly closed when not in use.

See also: Kuvan dosage (in more detail)

What happens if I miss a dose?

Take the missed dose as soon as you remember. If it is almost time for your next dose, wait until then to take the medicine and skip the missed dose. Do not take extra medicine to make up the missed dose.

Do not take 2 doses on the same day.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include headache and dizziness.

What should I avoid while taking Kuvan?

Follow your doctor's instructions about any restrictions on food, beverages, or activity while you are using Kuvan.

Kuvan side effects

If Kuvan is not controlling your condition properly, you may have symptoms such as behavior changes, numbness or tingling, or problems with speech, vision, or balance. Call your doctor right away if you have any of these symptoms.

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have any of the serious side effects below:

• seizure (convulsions);

• chest pain or heavy feeling, pain spreading to the arm or shoulder, general ill feeling;

• easy bruising or bleeding;

• fever, chills, body aches, flu symptoms;

• swelling in your hands or feet;

• pain or burning when you urinate;

• weakness or fainting;

• black, bloody, or tarry stools; or

• coughing up blood or vomit that looks like coffee grounds.

Less serious side effects may include:

• nausea, vomiting, stomach pain, diarrhea;

• runny or stuffy nose, cough;

• headache, feeling agitated;

• dizziness; or

• joint pain.

This is not a complete list of side effects and others may occur. Tell your doctor about any unusual or bothersome side effect. You may report side effects to FDA at 1-800-FDA-1088.

See also: Kuvan side effects (in more detail)

What other drugs will affect Kuvan?

The following drugs can interact with Kuvan. Tell your doctor if you are using any of these:

• levodopa (Larodopa, Altamet, Parcopa, Sinemet);

• methotrexate (Rheumatrex, Trexall);

• sildenafil (Viagra);

• tadalafil (Cialis); or

• vardenafil (Levitra).

This list is not complete and there may be other drugs that can interact with Kuvan. Tell your doctor about all your prescription and over-the-counter medications, vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start a new medication without telling your doctor.

Where can I get more information?

• Your pharmacist can provide more information about Kuvan.