Injectafer (ferric carboxymaltose) is a prescription drug that’s used to treat anemia caused by low iron levels. The drug comes as an injectable solution that’s given by injection or infusion. It’s usually given in one or two doses.

Injectafer is used to treat anemia caused by low iron levels. This is called iron deficiency anemia. Injectafer is prescribed:

The active ingredient in Injectafer is ferric carboxymaltose. (An active ingredient is what makes a drug work.) Injectafer belongs to a group of drugs called iron replacement products.

This article describes the dosages of Injectafer, as well as its strengths and how to take it. To learn more about Injectafer, see this in-depth article.

The table below highlights the basics of Injectafer’s dosage. Dosage for Injectafer is based on weight.

All doses are listed in milligrams per kilogram (mg/kg). Note that there are two dosage options for people weighing 50 kg — about 110 pounds (lb) — or more.

50 kg or more750 mg2 doses separated by at least 7 days
50 kg or more15 mg/kg up to 1,000 mgsingle dose
less than 50 kg15 mg/kg 2 doses separated by at least 7 days

Keep reading for more details about Injectafer’s dosage.

What is Injectafer’s form?

Injectafer is available as a liquid solution. It’s given either as a slow intravenous (IV) injection or as an infusion.

What strengths does Injectafer come in?

Injectafer comes as a single strength: 50 mg of elemental iron per milliliter (50 mg/mL). It’s available in single-dose vials in the following three sizes:

  • 100 mg/2 mL
  • 750 mg/15 mL
  • 1,000 mg/20 mL

What are the usual dosages of Injectafer?

The information below describes dosages that are commonly used or recommended. But your doctor will determine the best dosage to fit your needs.

Dosage for iron deficiency anemia

The typical Injectafer dosage for adults weighing 50 kg (110 lb) or more is two doses of 750 mg separated by at least 7 days. An alternative dosage is 15 mg/kg, up to a maximum of 1,000 mg, in a single dose. Adults weighing less than 50 kg receive 15 mg/kg in two doses separated by at least 7 days.

If your anemia recurs, your doctor may recommend repeating your treatment.

What’s the dosage of Injectafer for children?

Injectafer is used to help treat anemia caused by low iron levels in children ages 1 year and older.

The dosage used in children is the same as the dosage for adults weighing less than 50 kg (110 lb). If your child weighs less than 50 kg, they may receive 15 mg/kg in two doses separated by at least 7 days. But your child’s doctor will determine the best dosage to fit their needs.

For more information about Injectafer’s dosage for children, talk with your child’s doctor or a pharmacist.

Is Injectafer used long term?

No, Injectafer isn’t typically used as a long-term treatment. However, if your anemia recurs and your doctor determines that it’s needed, you may receive repeat treatment. Your doctor can tell you more.

The dosage of Injectafer you’re prescribed may depend on several factors. These include:

  • the severity of the condition you’re using the drug to treat
  • your weight

Injectafer is available as a liquid solution. It’s given either as a slow IV injection or as an infusion. A healthcare professional may prepare your dose differently depending on how they will be giving it.

A slow IV injection should take at least 15 minutes. If you receive your dose as an IV infusion, it will typically take 15–30 minutes.

You’ll receive the infusions at your doctor’s office or a clinic.

If you miss an appointment to receive a dose of Injectafer, call your doctor’s office as soon as possible to reschedule.

If you need help remembering your appointments, try setting an alarm or downloading a reminder app on your phone.

Below are answers to some commonly asked questions about Injectafer’s dosage.

Is Injectafer’s dosage similar to the dosages of Venofer?

Dosage varies between Injectafer and Venofer (iron sucrose). Injectafer’s dosage depends on your weight, while Venofer’s dosage depends on the condition you have and your age. Also, the number of doses given varies for each drug.

While their dosages vary, these drugs do have some similarities. Both Injectafer and Venofer come as liquid solutions that are given either by slow injection or by infusion. And both are given by a healthcare professional.

To learn more about how these drugs compare, talk with your doctor.

How long does it take for Injectafer to start working?

Injectafer starts to work after your first dose. Because of how the drug works, you likely won’t feel the drug working in your body. But your doctor will monitor you during treatment to check whether the drug is working to treat your condition. Your doctor may see an improvement in your iron levels after about 35 days.

If you have other questions about what to expect from your Injectafer treatment, talk with your doctor.

The sections above describe the usual dosages provided by Injectafer’s manufacturer. If your doctor recommends this drug, they’ll prescribe the dosage that’s right for you. Talk with your doctor if you have questions or concerns about your current dosage.

Here are some examples of questions you may want to ask your doctor:

  • How many doses of Injectafer do I need to resolve my anemia?
  • How is it decided which dosage is better for me — the higher dose in a single injection or the split dose over two separate injections?
  • If I need higher doses of Injectafer, which side effects may worsen?

To learn more about Injectafer, see these articles:

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Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.