Rapivab (peramivir) is a brand-name drug that’s prescribed for influenza virus (the flu) in adults and some children. Rapivab comes as a solution for intravenous (IV) infusion that’s given by a healthcare professional. The dosage can vary depending on your age.

Rapivab belongs to a drug class called neuraminidase inhibitors. Rapivab is not available in a generic version.

Rapivab has some limitations of use: Studies of Rapivab included mostly people with influenza A virus. So, it’s not known how well this medication may work in people who have influenza B virus. In addition, it’s not known whether this medication may be effective in people with severe influenza infections that require hospitalization.

Keep reading for specific information about the dosage of Rapivab, including its strength and how you’ll receive the medication. For a comprehensive look at Rapivab, see this article.

Note: This article describes typical dosages for Rapivab provided by the drug’s manufacturer. However, your doctor will prescribe the Rapivab dosage that’s right for you.

Below is information about Rapivab’s recommended dosages.

Rapivab form

Rapivab comes as a solution that’s given as an IV infusion. It’s always given by a healthcare professional. You’ll receive your dose in a clinic or hospital.

Rapivab strength

Rapivab comes in one strength of 200 milligrams in 20 milliliters of solution (mg/mL). The concentration of Rapivab is 10 mg/mL.

Typical dosages

The following information describes dosages that are commonly prescribed in adults. However, your doctor will determine the dosage that’s best for you.

Dosage for influenza

Doctors may prescribe Rapivab to treat acute influenza infection.

If your doctor prescribes Rapivab for your influenza infection, your dose will be 600 mg. Typically, you’ll receive this dose within 2 days of your flu symptoms starting. You’ll only need to get one dose of Rapivab to treat your influenza infection.

For more information about your specific dosage, talk with your doctor.

Children’s dosage

Rapivab is approved to treat influenza infection in children ages 6 months and older.

The dosage is based on the child’s body weight in kilograms (kg). One kg equals about 2.2 pounds (lb). The dosage per kg is measured in milligrams per kilogram (mg/kg) and is calculated by your child’s doctor. The recommended dosage of Rapivab for children 6 months to 12 years old is 12 mg/kg. So, if your child weighs 66 lb (30 kg), their dose will be 360 mg. The maximum recommended dose is 600 mg.

Children 13 years and older will take the adult dose of Rapivab. They’ll receive a dose of 600 mg.

Your child will only need one dose of Rapivab to treat their influenza infection. Talk with your child’s doctor if you have questions about their dosage.

Long-term treatment

Rapivab is a short-term treatment for influenza infections. Doctors prescribe Rapivab for one dose only.

Talk with your doctor if you have questions about how long you can expect to take Rapivab.

The Rapivab dosage your doctor prescribes will depend on several factors. These include:

  • your age
  • your body weight
  • your kidney function

Other medical conditions you have can also affect your Rapivab dosage.

Dosage adjustments

Your doctor may need to adjust your dosage if you have kidney disease.

Be sure to tell your doctor about all medications you take and any health conditions you may have.

Your doctor or another healthcare professional will give you the IV infusion of Rapivab. First, they’ll prepare the liquid solution for infusion by diluting it. You’ll likely go to your doctor’s office, infusion center, or a hospital to receive your infusion. The infusion takes about 15–30 minutes.

If you have questions about how to use Rapivab, talk with your doctor or pharmacist.

Below are some frequently asked questions about Rapivab.

Is the dosage of Rapivab similar to the dosage of Xofluza?

Yes, how often you take Rapivab and Xofluza are the same. You’ll only need one dose of either Rapivab or Xofluza for your influenza infection.

However, Rapivab and Xofluza are available in different forms and are taken or received very differently. Both drugs are used to treat influenza infections. But Rapivab comes as a solution that’s given as an IV infusion. It’s given by a healthcare professional in a hospital or clinic. In comparison, Xofluza is available as a tablet or liquid suspension that’s taken by mouth. You can take your Xofluza at home, so you don’t need to be in a hospital or clinic.

The dose in mg for each drug differs because they have different active ingredients. Your doctor will prescribe the drug and the dosage that’s right for you.

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

How long does it take for Rapivab to start working?

Rapivab starts to work as soon as you get your dose of medication. In fact, the drug is at its highest level in your body right after you receive your infusion. But because of how the drug works, you may not feel it working right away. Your doctor will monitor you during treatment to check whether the drug is working to treat your condition.

Talk with your doctor if you have questions about what to expect with Rapivab treatment.

The dosages in this article are typical dosages provided by the drug’s manufacturer. If your doctor recommends Rapivab for you, they will prescribe the dosage that’s right for you.

Besides learning about dosage, you may want other information about Rapivab. These additional articles might be helpful:

  • More about Rapivab: For information about other aspects of Rapivab, refer to this article.
  • Side effects: To learn about side effects of Rapivab, see the Rapivab prescribing information.

Disclaimer: Medical News Today 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.