This medication is used to improve survival from a certain genetic disorder (molybdenum cofactor deficiency-MoCD Type A). Fosdenopterin replaces a certain substance that is missing in people with MoCD Type A.

How to use Fosdenopterin 9.5 Mg Intravenous Solution

Read the Instructions for Use if available from the pharmacist before your child starts using fosdenopterin and each time you get a refill. If you have any questions, ask the doctor or pharmacist.

This medication is given by injection into a vein as directed by your child's doctor, usually once a day.

If you are using this medication at home, learn all preparation and usage instructions from the health care professional. The medication in the vial and the supplies that come with the medication should be used only once. Do not reuse. Take fosdenopterin out of the freezer 30 minutes before use to allow it to reach room temperature. You may also gently roll the vial in between your hands for 3 to 5 minutes. The solution used to mix the medication should also be at room temperature. After adding the solution to the powder, gently swirl the mixture to completely dissolve the powder. Do not shake. Check this product visually for particles or discoloration. If either is present, do not use the liquid. Learn how to store and discard medical supplies safely.

Use this medication regularly to get the most benefit from it. To help you remember, use it at the same time each day.

Do not increase the dose or use this drug more often or for longer than prescribed. Your child's condition will not improve any faster, and your child's risk of side effects will increase.

Tell the doctor if your child's condition gets worse.

Side Effects

Redness, pain, or swelling at the injection site may occur. If any of these effects last or get worse, tell the doctor or pharmacist promptly.

Remember that this medication has been prescribed because the doctor has judged that the benefit to your child is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell the doctor right away if your child has any serious side effects, including: skin blisters/redness.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.


Before using fosdenopterin, tell the doctor or pharmacist if your child is allergic to it; or if your child has any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to the pharmacist for more details.

Before using this medication, tell your child's doctor or pharmacist your child's medical history.

This medication may make your child more sensitive to the sun. Limit your child's time in the sun. Avoid tanning booths and sunlamps. Use sunscreen and wear protective clothing when outdoors. Tell the doctor right away if your child gets sunburned or has skin blisters/redness. The doctor may direct your child to limit or avoid phototherapy while your child uses this product. Ask the doctor for details.

Before having surgery, tell the doctor or dentist about all the products your child uses (including prescription drugs, nonprescription drugs, and herbal products).

This medication is not usually used by adults. It is unlikely to be used during pregnancy or breastfeeding. Consult your doctor if you have any questions about this medication.


Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

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If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.

Notes Notes

Do not share this medication with others.

Missed Dose Missed Dose

It is important that your child gets each dose of this medication as scheduled. If your child misses a dose, give it as soon as you remember. Make sure there are at least 6 hours between the missed dose and the next scheduled dose. Do not double the dose to catch up.

Storage Storage

Store the unmixed vial in the original carton in the freezer away from light. The mixing solution may be kept at room temperature. After mixing, use this medication right away or within 4 hours. Do not freeze the mixed solution. Discard any unused portion. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.


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Selected from data included with permission and copyrighted by First Databank, Inc. This copyrighted material has been downloaded from a licensed data provider and is not for distribution, except as may be authorized by the applicable terms of use.

CONDITIONS OF USE: The information in this database is intended to supplement, not substitute for, the expertise and judgment of healthcare professionals. The information is not intended to cover all possible uses, directions, precautions, drug interactions or adverse effects, nor should it be construed to indicate that use of a particular drug is safe, appropriate or effective for you or anyone else. A healthcare professional should be consulted before taking any drug, changing any diet or commencing or discontinuing any course of treatment.