Xofluza 80 Mg Dose Pack (baloxavir marboxil) is a single-dose prescription antiviral medication used to treat influenza (the flu) in patients 5 years of age and older.

What Is Xofluza?

Xofluza is the brand name for baloxavir marboxil, a prescription antiviral made by Genentech (a member of the Roche Group). It belongs to a class of drugs called cap-dependent endonuclease inhibitors — a different mechanism from older flu medications like Tamiflu (oseltamivir).

What makes Xofluza unique is its dosing: it's a single-dose treatment. You take one dose by mouth and you're done. There's no five-day course of pills to remember. The 80 Mg Dose Pack contains the dose for patients weighing 80 kg (about 176 pounds) or more.

Xofluza was first approved by the FDA in 2018 and has since expanded its approved uses to include treatment and prevention of influenza. To understand how it works at a deeper level, see our guide on Xofluza's mechanism of action.

FDA-Approved Uses

Xofluza is FDA-approved for three specific uses:

1. Treatment of acute uncomplicated influenza in otherwise healthy patients 5 years and older who have been symptomatic for no more than 48 hours.
2. Treatment of acute uncomplicated influenza in high-risk patients 5 years and older who have been symptomatic for no more than 48 hours. High-risk groups include people with asthma, chronic lung disease, heart disease, diabetes, obesity, weakened immune systems, and adults 65 and older.
3. Post-exposure prophylaxis (prevention) of influenza in patients 5 years and older after close contact with someone who has the flu.

Xofluza works against both influenza A and influenza B viruses.

How Is Xofluza 80 Mg Dose Pack Taken?

Xofluza 80 Mg Dose Pack is taken as a single oral dose. Here's what you need to know:

• Timing: Take it within 48 hours of your first flu symptoms. The sooner, the better.
• With or without food: You can take Xofluza with or without food.
• What to avoid: Do not take Xofluza with dairy products (milk, cheese, yogurt), calcium-fortified beverages, or supplements containing calcium, iron, magnesium, selenium, or zinc. These can reduce how well the medication is absorbed.
• Dose is weight-based: The 80 mg dose is for patients weighing 80 kg (176 lbs) or more. Patients between 40 kg and 80 kg take 40 mg instead.

Who Should Not Take Xofluza?

Xofluza should not be taken by anyone with a known allergy (hypersensitivity) to baloxavir marboxil or any ingredient in the product. Additionally:

• Children under 5: Xofluza is not approved for children younger than 5 years old.
• Weight restrictions for tablets: The tablet form requires a minimum weight of 40 kg (about 88 lbs). Children who weigh less may use the oral suspension form if they're 5 or older and weigh at least 20 kg.
• Pregnancy and breastfeeding: Limited data is available. Talk to your doctor about the benefits and risks.
• Live flu vaccine timing: Avoid taking Xofluza within 2 weeks before or 48 hours after receiving the live attenuated influenza vaccine (FluMist), as Xofluza may reduce the vaccine's effectiveness.

Side Effects

Most people tolerate Xofluza well. The most common side effects reported in clinical trials include diarrhea (3%), bronchitis (3%), nausea (2%), sinusitis (2%), and headache (1%). Serious allergic reactions are rare but possible. For a complete breakdown, see our detailed guide to Xofluza side effects.

How Much Does Xofluza 80 Mg Dose Pack Cost?

Without insurance, Xofluza 80 Mg Dose Pack typically costs between $200 and $280 at retail pharmacies. There is no generic version available as of 2026.

However, several options can significantly lower the cost:

• Manufacturer coupon: Eligible commercially insured patients may pay as little as $35, with up to $70 off.
• Direct-to-patient program: A $50 cash-pay option is available through select pharmacies including Alto Pharmacy, Amazon Pharmacy, and Cost Plus Drugs — up to 70% lower than list price.
• Patient assistance: The Genentech Patient Foundation may help uninsured or underinsured patients. Call 1-877-GENENTECH (436-3683).

For a complete rundown of savings options, see our guide to saving money on Xofluza.

Final Thoughts

Xofluza 80 Mg Dose Pack is a convenient, single-dose flu treatment that works differently from older antivirals like Tamiflu. It's approved for treatment and prevention of influenza in patients 5 and older, and it's available through a prescription from most primary care providers, urgent care clinics, and telehealth services.

If you're looking for Xofluza near you, Medfinder can help you find a pharmacy with it in stock. And if you need a prescription, our guide to finding a prescriber can help you get started.