Xofluza (baloxavir marboxil) is a brand-name prescription medication. The Food and Drug Administration (FDA) has approved it for use in certain situations to:
- treat non-severe influenza (flu) in people ages 5 years or older who’ve had symptoms for less than 48 hours
- treat non-severe flu in people ages 12 years or older who are at high risk of having serious problems from the flu
- help prevent flu in people ages 5 years or older who’ve come in close contact with someone who has the flu
Xofluza is an influenza antiviral medication that belongs to the polymerase acidic endonuclease inhibitor drug class. Xofluza comes as both an oral tablet and an oral suspension. It’s not available in a generic form.
For information about Xofluza’s dosage, including a dosing chart and how to take the drug, keep reading. For a comprehensive look at Xofluza, see this article.
This article describes typical dosages of Xofluza provided by the drug’s manufacturer. When taking Xofluza, always follow the dosage prescribed by your doctor.
Your doctor will recommend a dosage of Xofluza that’s best for you. You should always take Xofluza exactly as your doctor prescribes. See the “Factors that can affect your dosage” section below for information on how doctors may decide on the dosage you should take.
Xofluza forms
Xofluza comes in two forms: an oral tablet and an oral suspension. (The oral suspension is a liquid form that is made by a healthcare professional.) Both forms are taken by mouth.
Xofluza strengths
Xofluza oral tablets are available in strengths of:
- 40 milligrams (mg)
- 80 mg
Xofluza oral suspension is available in a strength of 2 mg per milliliter (mg/mL). It comes in a bottle containing 40 mg/20 mL.
Typical dosages
To treat influenza (flu), Xofluza should be taken as a one-time dose within 48 hours of the beginning of your flu symptoms.
To help prevent the flu, Xofluza should be taken as a one-time dose after you’ve been in close contact with someone who has the flu.
For these purposes, you can take either the oral tablets or oral suspension, depending on which one your doctor prescribes.
The following information describes dosages that are commonly used or recommended. However, be sure to take the dosage your doctor prescribes for you. Your doctor will determine the best dosage to fit your needs.
Dosage for adults to help prevent or treat the flu
The recommended dosage of Xofluza in adults for flu treatment and prophylaxis (prevention) is the same. Doctors recommend Xofluza dosages by weight, as shown in the chart below. For reference, 1 kilogram (kg) is equal to about 2.2 pounds (lb).
The following chart describes the drug’s flu treatment dosage and flu prophylaxis dosage. Xofluza oral tablet or oral solution is taken as a one-time dose.
| Body weight (kg) | Body weight (lb) | Recommended oral tablet dose | Recommended oral suspension dose |
| 20 kg to less than 80 kg | about 44 lb to 175 lb | one 40-mg tablet | 40 mg, which is 20 mL |
| 80 kg or more | about 176 lb or more | one 80-mg tablet | 80 mg, which is 40 mL |
Children’s dosage
Xofluza’s recommended dosages in children are very similar to those in adults. Doctors also recommend children’s Xofluza doses based on weight. For reference, 1 kilogram (kg) is equal to about 2.2 pounds (lb).
Recommended Xofluza doses for children are shown in the chart below. Xofluza oral tablet or oral solution is taken as a one-time dose.
| Body weight (kg) | Body weight (lb) | Recommended oral tablet dose | Recommended oral suspension dose |
| less than 20 kg | about 43 lb or less | not recommended | 2 mg/kg of body weight |
| 20 kg to less than 80 kg | about 44 lb to 175 lb | one 40-mg tablet | 40 mg, which is 20 mL |
| 80 kg or more | about 176 lb or more | one 80-mg tablet | 80 mg, which is 40 mL |
Length of treatment
Xofluza is meant to be a short-term treatment of only one dose. It’s not used as a long-term treatment.
The Xofluza dosage your doctor prescribes will depend on several factors. These include:
- the type and severity of the condition you’re taking Xofluza to treat
- your age
- your weight
Xofluza comes as an oral tablet and an oral suspension. (The oral suspension is a liquid form that is made by a healthcare professional.) Both forms are taken by mouth.
You should swallow the oral tablets whole. You can take them with or without food. That said, you should not take Xofluza with dairy products or products that are high in calcium, such as milk or cheese.
You should drink the oral suspension while sitting upright. Do not lie down before drinking it, and do not mix it with any soft foods or liquids.
Your pharmacist will make the oral suspension for you before you pick it up from the pharmacy. It’s important to know that Xofluza oral suspension must be taken within 10 hours after it’s mixed by your pharmacist. Your bottle of Xofluza oral suspension will have an expiration time marked on it to let you know the time it should be taken by.
If you have trouble swallowing tablets, see this article for tips on how to take this form of medication. You can also talk with your doctor or pharmacist to find out whether they can prescribe the oral suspension for you instead.
ACCESSIBLE DRUG LABELS AND CONTAINERSIf you’re having trouble reading your prescription label, talk with your doctor or pharmacist. Some pharmacies offer labels with large print, braille, or a code you scan with a smartphone to convert text to speech. If your local pharmacy doesn’t have these options, your doctor or pharmacist might be able to recommend a pharmacy that does.
If you’re having trouble opening medication bottles, ask your pharmacist about putting Xofluza in an easy-open container. They also may recommend tools that can make it easier to open bottles.
It’s important that you do not take more Xofluza than your doctor prescribes. For some medications, taking more than the recommended amount may lead to side effects or overdose.
If you take more than the recommended amount of Xofluza
Call your doctor right away if you believe you’ve taken too much Xofluza. Another option is to call the American Association of Poison Control Centers at 800-222-1222 or use its online tool. If you have severe symptoms, immediately call 911 or your local emergency number, or go to the nearest emergency room.
Below are some common questions about Xofluza. If you have any other questions related to Xofluza, talk with your doctor or pharmacist.
Can I still get influenza (flu) after I have taken a Xofluza dose for prevention?
Yes, you can still get influenza (flu) even if you took Xofluza to help prevent it.
In the drug’s clinical trials, people who took Xofluza after coming into contact with someone who had the flu were much less likely to be diagnosed with it. A small percentage of people did get the flu after taking Xofluza. However, significantly fewer people developed the flu compared with those who did not take Xofluza for this purpose.
If you have additional questions about flu prevention, talk with your doctor. They can also discuss other preventive measures, such as receiving a flu vaccine.
How long does it take for Xofluza to start working?
Xofluza will start working 4 hours after you take a dose. In the drug’s clinical trials, people taking Xofluza as prescribed had their flu symptoms resolve about 1 day sooner than people who didn’t take the drug.
If your flu symptoms aren’t resolving or they’re worsening after taking Xofluza, call your doctor right away. They can recommend how to manage your condition.
The dosages described in this article are typical dosages provided by the drug manufacturer. If your doctor recommends Xofluza for you, they will prescribe the dosage that’s right for you. Always follow the dosage that your doctor prescribes.
As with any drug, never change your dosage of Xofluza without your doctor’s recommendation. If you have questions about the dosage of Xofluza that’s best for you, talk with your doctor.
Besides learning about dosage, you may want other information about Xofluza. These additional articles might be helpful:
- More about Xofluza. For information about other aspects of Xofluza, refer to this article.
- Drug comparison. Find out how Xofluza compares with Tamiflu and Relenza.
- Details about influenza. For details about influenza (flu), see our flu hub.
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.
