Xofluza Dosages: Your GoodRx Guide

A sudden fever, fatigue, and muscle aches — these are all possible symptoms of seasonal influenza, also known as the flu. They can come on quickly and last more than a week. So finding quick treatment is a priority if you end up being exposed to this respiratory virus.

Xofluza (baloxavir marboxil) is one flu medication your healthcare provider may recommend. Xofluza is an FDA-approved antiviral medication that can treat or prevent the flu with a single dose. Many adults and children can take it.

But, like with all medications, Xofluza’s safety and effectiveness hinges on the right dose. This guide reviews recommended Xofluza dosages for flu treatment and prevention. But make sure to speak to your healthcare provider about the best dosage for you — it may be different from what’s mentioned here.

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How is Xofluza supplied?

Xofluza is available as an oral tablet and liquid. The tablet comes in two dosages (40 mg and 80 mg), and the liquid is available as one concentration (40 mg/20 mL).

Regardless of form, Xofluza is a one-time, oral medication. This makes it convenient to take, but timing is key. It should be taken within 48 hours (2 days) of flu symptoms first appearing. So, if you start feeling sick or you come into contact with someone who has the flu, it’s important to see a healthcare provider for a flu test as soon as possible.

You can take Xofluza with or without food. But there are a few things to keep in mind if you’re taking Xofluza with a meal or snack. For example, don’t take it at the same time as dairy products or drinks fortified with calcium. Oral supplements containing iron, magnesium, or zinc can also pose an issue. These interactions can make Xofluza less effective.

What’s the typical Xofluza dosage for adults?

Xofluza can be used for flu treatment and flu prevention in adults.

Flu treatment

If you’re prescribed Xofluza, your healthcare provider will calculate your dose based on your body weight in kilograms (kg). These are the recommended Xofluza dosages to treat flu in adults.

For Xofluza liquid dosing, it’s important to use a measuring device — specifically an oral syringe — to measure an exact dose. Household spoons and other similar tools often provide incorrect or inaccurate doses.

Good to know: If you’re prescribed 80 mg of liquid Xofluza, your pharmacist will provide you with two bottles of medication. Smaller, 40 mg doses only need one bottle. But regardless of size, the pharmacist needs to prepare the liquid for you. It should be taken within 10 hours of mixing. The pharmacist can also add flavoring to make the medication more appealing.

Flu prevention

Recommended Xofluza dosages for flu prevention are the same as flu treatment. These are detailed in the table above.

What’s the typical Xofluza dosage for children?

Xofluza pediatric doses are similar to adult doses. Your child may be able to take Xofluza if it’s been less than 48 hours since their flu symptoms started or they came in contact with someone who had the flu.

They should also meet at least one these qualifications:

• Flu treatment: The child is at least 5 years old and is considered healthy (aside from the flu).

• Flu treatment: The child is at least 12 years old, and they have a high risk of developing flu-related complications.

• Flu prevention: They’re at least 5 years old — regardless of health background.

Flu treatment

Like adults, Xofluza dosages for kids are based on body weight. But depending on how much your child weighs, your healthcare provider may have to do some extra calculations to figure out their dose.

You won’t need to figure out a dosage on your own. But weight-based dosing can still be hard to visualize. If your child weighs 10 kg (22 lbs), they would need 20 mg of liquid Xofluza. This amounts to 10 mL of medication. Your pharmacist should provide you with a measuring device so you can administer the prescribed dose.

Flu prevention

If your child comes in close contact with someone who has the flu, they can take Xofluza for flu prevention if they’re at least 5 years old. The recommended doses for children are the same as for flu treatment, listed above.

Keep in mind: Xofluza is not approved for use in children younger than 5 years old. Younger kids shouldn’t take Xofluza because there is a risk of “treatment-emergent resistance.” In other words, Xofluza may not work as well and the flu virus can become harder to treat in the future. Xofluza’s safety and effectiveness in younger kids also isn’t well established.

Are there any dosage adjustments for medical conditions?

Not usually. Xofluza doesn’t have recommended dosage adjustments for specific medical conditions. This includes kidney and liver problems.

However, some people should avoid taking Xofluza altogether. If you’ve had an allergic reaction in the past to any of Xofluza’s ingredients, you shouldn’t take it. Pregnant women should also avoid taking Xofluza out of caution. Tamiflu (oseltamivir) is preferred during pregnancy.

What happens if you miss a dose of Xofluza?

In most cases, missed doses shouldn’t be an issue. Xofluza is taken as a single dose. Repeat doses aren’t usually necessary.

Still, try to take your dose as soon as possible — especially within 48 hours of developing flu symptoms or after coming in contact with someone who has the flu. If you don’t take Xofluza within the recommended time frame, the medication may be less effective.

What should you do if you take too much Xofluza?

Xofluza overdoses aren’t common, but they could technically happen.

If you think you took too much Xofluza (or gave your child too much), call your healthcare provider as soon as you can. They’ll aim to address any symptoms or side effects you may be experiencing, such as diarrhea or nausea. You can also call Poison Control at 1-800-222-1222.

If you feel that you’re having serious or life-threatening symptoms, go to the nearest emergency room right away.

How to save on Xofluza

There are ways to save on Xofluza, which is only available as a brand-name medication. GoodRx can help you navigate between copay savings cards and other discounts to save money on your prescription.

• Save with a copay savings card. If you have commercial insurance, you may be eligible to pay as little as $30 for Xofluza using a savings card from the manufacturer.

• Save with GoodRx. GoodRx can help you save over 20% off the average retail price of Xofluza. Xofluza’s price at certain pharmacies is as low as $166.17 with a free GoodRx discount.

Why trust our experts?

Written by:

Tanya Kertsman, PharmD

Tanya Kertsman has been a licensed pharmacist in New Jersey and Pennsylvania for 13 years. She has worked in the pharmaceutical industry in medical affairs for 7 years, developing and reviewing medical content for consumers and healthcare professionals.

Edited by:

Joshua Murdock, PharmD, BCBBS

Joshua Murdock, PharmD, BCBBS, is a licensed pharmacist in Arizona, Colorado, and Rhode Island. He has worked in the pharmacy industry for more than 10 years and currently serves as a pharmacy editor for GoodRx.

Reviewed by:

Stacia Woodcock, PharmD

Stacia Woodcock, PharmD, is a pharmacy editor for GoodRx. She earned her Doctor of Pharmacy degree from the University of Kentucky and is licensed in New York and Massachusetts.

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