Generic name: sapropterin [ sap-roe-TER-in ]
Drug class: Miscellaneous metabolic agents
Medically reviewed by Drugs.com. Last updated on Nov 21, 2023.
Uses for sapropterin
Sapropterin is used to lower phenylalanine levels in the blood of patients with phenylketonuria (PKU). High levels of phenylalanine (an amino acid) in the blood can cause severe brain damage, including severe mental retardation, seizures, tremors, or decreased learning ability. This medicine is usually given along with a special diet.
This medicine is available only with your doctor's prescription.
Before using sapropterin
In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. This is a decision you and your doctor will make. For this medicine, the following should be considered:
Tell your doctor if you have ever had any unusual or allergic reaction to this medicine or any other medicines. Also tell your health care professional if you have any other types of allergies, such as to foods, dyes, preservatives, or animals. For non-prescription products, read the label or package ingredients carefully.
Appropriate studies have not been performed on the relationship of age to the effects of sapropterin in children younger than 1 month of age. Safety and efficacy have not been established. .
Appropriate studies on the relationship of age to the effects of sapropterin have not been performed in the geriatric population. Safety and efficacy have not been established.
There are no adequate studies in women for determining infant risk when using this medication during breastfeeding. Weigh the potential benefits against the potential risks before taking this medication while breastfeeding.
Interactions with Medicines
Although certain medicines should not be used together at all, in other cases two different medicines may be used together even if an interaction might occur. In these cases, your doctor may want to change the dose, or other precautions may be necessary. When you are taking this medicine, it is especially important that your healthcare professional know if you are taking any of the medicines listed below. The following interactions have been selected on the basis of their potential significance and are not necessarily all-inclusive.
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Interactions with Food/Tobacco/Alcohol
Certain medicines should not be used at or around the time of eating food or eating certain types of food since interactions may occur. Using alcohol or tobacco with certain medicines may also cause interactions to occur. Discuss with your healthcare professional the use of your medicine with food, alcohol, or tobacco.
Other Medical Problems
The presence of other medical problems may affect the use of this medicine. Make sure you tell your doctor if you have any other medical problems, especially:
- Brain disease or
- Seizures—May make these conditions worse if taken with levodopa.
- Eating disorder (eg, anorexia) or
- Malnutrition—Proper diet is important while taking this medicine.
- Fever or any illness—May increase phenylalanine levels in your blood. Your doctor may need to change your dose of this medicine.
- Hypotension (low blood pressure) or
- Liver disease—Use with caution. May make these conditions worse.
- Kidney disease—Use with caution. This medicine has not been tested in patients with this condition.
Proper use of sapropterin
Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered. To do so may increase the chance of side effects.
This medicine should come with a patient information insert. Read and follow these instructions carefully. Ask your doctor if you have any questions.
It is best to take this medicine with food at the same time each day.
Carefully follow your doctor's instructions about any special diet. It is important that you maintain a diet with restricted amounts of phenylalanine.
Patients who weigh more than 10 kilograms who are using the powder for oral solution: Pour the contents of the 100 mg- or 500 mg- packet in 4 to 8 ounces (1/2 to 1 cup) of water or apple juice. Mix thoroughly. Drink this mixture within 30 minutes. You may also add it in a small amount of food, such as applesauce or pudding before taking.
Patients who weigh more than 10 kilograms who are using the tablets: You may swallow the tablets whole or mix them in 4 to 8 ounces (1/2 to 1 cup) of water or apple juice before taking. It may take a few minutes for the tablets to dissolve. To make the tablets dissolve faster, you may stir or crush them. Drink this mixture within 15 minutes. You may also crush the tablets and mix in a small amount of soft food, such as apple sauce or pudding before taking.
The dose of this medicine will be different for different patients. Follow your doctor's orders or the directions on the label. The following information includes only the average doses of this medicine. If your dose is different, do not change it unless your doctor tells you to do so.
The amount of medicine that you take depends on the strength of the medicine. Also, the number of doses you take each day, the time allowed between doses, and the length of time you take the medicine depend on the medical problem for which you are using the medicine.
- For oral dosage forms (solution or tablets):
- Adults and children 7 years of age and older—Dose is based on body weight and must be determined by your doctor. The starting dose is usually 10 to 20 milligrams (mg) per kilogram (kg) of body weight per day. Your doctor may adjust your dose if needed.
- Children 1 month to 6 years of age—Dose is based on body weight and must be determined by your doctor. The starting dose is usually 10 mg per kg of body weight per day. Your doctor may adjust your dose if needed.
- Children younger than 1 month of age—Use and dose must be determined by your doctor.
If you miss a dose of this medicine, take it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not double doses.
Keep out of the reach of children.
Do not keep outdated medicine or medicine no longer needed.
Ask your healthcare professional how you should dispose of any medicine you do not use.
Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light. Keep from freezing.
Keep the bottle tightly closed. Keep the medicine in the original bottle that you were given at the pharmacy.
Precautions while using sapropterin
It is very important that your doctor check your or your child's progress at regular visits to make sure this medicine is working properly. Blood tests may be needed to check for unwanted effects.
This medicine may cause serious allergic reactions, including anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Call your doctor right away if you have a rash, itching, lightheadedness or fainting, trouble breathing, trouble swallowing, or any swelling of your hands, face, or mouth while you or your child are using this medicine.
This medicine may cause esophagitis (inflammation of the esophagus) and gastritis (inflammation of the stomach). Check with your doctor right away if you or your child have a burning feeling in the chest or stomach, heartburn, indigestion, pain or burning in the throat, stomach upset, tenderness in the stomach area, trouble swallowing.
This medicine may cause hyperactivity (too much or constant activity). Tell your doctor if you or your child have any signs of the following: fidgeting or moving around too much or talking too much.
Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.
Side Effects of sapropterin
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Incidence not known
- Burning feeling in the chest or stomach
- difficulty with swallowing
- fast heartbeat
- fidgeting or moving around too much
- pain or burning in the throat
- puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue
- skin rash, hives, or itching
- sores, ulcers, or white spots on lips or tongue or inside the mouth
- stomach upset
- talking too much
- tenderness in the stomach area
- tightness in the chest
- trouble swallowing
- unusual tiredness or weakness
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
- runny nose
- sore throat
- Stuffy nose
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
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