What is Kuvan: Uses, Warnings & Interactions

Updated May 14, 2025  •  Published Jan 25, 2021

Kuvan overview

BRAND NAMES:

  • Kuvan

Generic Names:

  • Sapropterin Dihydrochloride

Uses:

  • Lowers phenylalanine levels in the blood.

Therapeutic Classes:

  • Endocrine-Metabolic Agent

Forms:

  • Liquid, Dissolving Tablet

How it’s taken:

  • By mouth

What is Kuvan used for?

Kuvan is prescribed for use by both adults and children who suffer from mental symptoms caused by Phenylketonuria. Phenylketonuria is a genetic condition that affects the nervous system. Kuvan is available as an oral powder for reconstitution and as an oral tablet, dispersible.

What form(s) does Kuvan come in

  • Liquid

  • Dissolving Tablet

What are common Kuvan doses?

  • Tablet Soluble 100MG

Common Kuvan prescriptions

  • Kuvan
    100mg packet

  • Kuvan
    100mg tablet

How to take Kuvan

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.

  • Take this medicine at the same time each day. Oral routeIt is best to take this medicine with food or milk.

  • Tablet: Swallow the tablets whole or mix them in 4 to 8 ounces (120 to 240 mL) of water or apple juice. You may stir or crush the tablets to help them dissolve faster. Drink this mixture within 15 minutes. You may also mix the crushed tablets into a small amount of soft food, including applesauce or pudding.

  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.

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

  • Powder for solution: Pour the contents of the 100 mg- or 500 mg- packet in 4 to 8 ounces (120 to 240 mL) of water or apple juice. Mix thoroughly. Drink this mixture within 30 minutes. You may also add the powder to a small amount of soft food, including applesauce or pudding. For infants weighing less than 10 kilograms, you may mix the medicine in as little as 5 mL of water or apple juice and give it to an infant by using an oral dosing syringe.

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep the bottle tightly closed. Keep the medicine in the original bottle that you were given at the pharmacy.

  • Tablet: Swallow the tablets whole or mix them in 4 to 8 ounces (120 to 240 mL) of water or apple juice. You may stir or crush the tablets to help them dissolve faster. Drink this mixture within 15 minutes. You may also mix the crushed tablets into a small amount of soft food, including applesauce or pudding.

  • Take your medicine as directed. Your dose may need to be changed several times to find what works best for you.

  • Powder for solution: Pour the contents of the 100 mg- or 500 mg- packet in 4 to 8 ounces (120 to 240 mL) of water or apple juice. Mix thoroughly. Drink this mixture within 30 minutes. You may also add the powder to a small amount of soft food, including applesauce or pudding. For infants weighing less than 10 kilograms, you may mix the medicine in as little as 5 mL of water or apple juice and give it to an infant by using an oral dosing syringe.

  • Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep the bottle tightly closed. Keep the medicine in the original bottle that you were given at the pharmacy.

  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.

  • Take this medicine at the same time each day. Oral routeIt is best to take this medicine with food or milk.

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

What to do if you miss a dose of Kuvan

Kuvan contraindications

  • This medicine is not right for everyone. Do not use it if you had an allergic reaction to sapropterin.

Kuvan warnings

  • Tell your doctor if you are pregnant or breastfeeding, or if you have kidney problems, liver problems, low blood pressure, brain disease, seizures, or a fever or any illness.

  • This medicine may cause esophagitis or gastritis, which can be severe.

  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Kuvan interactions

  • Some foods and medicines can affect how sapropterin works. Tell your doctor if you are using any of the following: Avanafil, levodopa, methotrexate, sildenafil, tadalafil, vardenafilAn antifolate medicine

  • This medicine may cause gastritis, which can be severe.

  • Oral routeCarefully follow your doctor's instructions about any special diet. Any changes to your diet can affect the phenylalanine level in your blood. Talk to your doctor before you make changes to the foods you eat.

  • Your doctor will do lab tests at regular visits to check on the effects of this medicine. Keep all appointments.

  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Kuvan side effects

Serious Side Effects

  • Restlessness, trouble sitting still or focusing

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing

  • Burning feeling in your chest or stomach, heartburn, upset stomach, vomiting, bloody or black stools

  • Lightheadedness, dizziness, fainting

  • Warmth or redness in your face, neck, arms, or upper chest

  • Trouble swallowing

Less Serious Side Effects

  • Diarrhea

  • Headache

  • Runny or stuffy nose, cough, sore throat