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The flu is serious. Treat it seriously

The flu can hit you fast and leave you with debilitating symptoms that last for more than a week. And it’s not just you. The CDC estimates that each year, up to 41 million people will be affected by the flu.* It can also lead to serious complications.

Look out for 3 common flu symptoms:

XOFLUZA® (baloxavir marboxil)

You don’t have to have all of the symptoms above to have the flu. If you’re experiencing any symptoms, don’t wait for things to get worse—contact your doctor when they first appear.

Is it the flu or COVID-19?

It is difficult to tell the difference between COVID-19 and the flu because some of the symptoms can be similar.

If you have COVID-19 or flu-like symptoms, contact your doctor. If it is the flu, you may be able to treat it with prescription XOFLUZA. But keep in mind, XOFLUZA does not treat COVID-19.

Is it a cold or the flu?

It can also be tough to tell the difference between a cold and the flu. But one sign of the flu is the way its symptoms come on fast. Use the chart below to check your symptoms.

If you think you have the flu, talk to your doctor within the first 48 hours of flu symptoms and ask if prescription one-dose XOFLUZA is right for you.

Signs and Symptoms Flu Cold
Symptom onset Abrupt Gradual
Fever Usual Rare
Aches Usual Slight
Chills Fairly common Uncommon
Fatigue, weakness Usual Sometimes
Sneezing Sometimes Common
Stuffy nose Sometimes Common
Sore throat Sometimes Common
Chest discomfort, cough Common Mild to moderate
Headache Common Rare

Attack the flu virus at its source with XOFLUZA

In certain patients who are at risk for complications, the CDC recommends treating the flu with a prescription medication within the first 48 hours of experiencing symptoms.* People with mild illness, who are not at risk for complications, may also be treated early with prescription one-dose XOFLUZA.

Over-the-counter medicines just treat symptoms. Prescription XOFLUZA works differently with only one dose to attack the flu virus at its source.

*Source: Centers for Disease Control and Prevention (CDC). The CDC does not endorse private products, services, or enterprises. The content provided is for informational purposes only. Find the latest at

Important Safety Information & Indication

What is XOFLUZA?

XOFLUZA is a prescription medicine used to:

  • treat the flu (influenza) in people who have flu symptoms for no more than 48 hours and who are:
    • otherwise healthy adults and children 5 years of age and older, or
    • adults and children 12 years of age and older who are at high risk of developing problems from the flu.
  • prevent the flu in people 5 years of age and older following contact with a person who has the flu (post-exposure prophylaxis).

XOFLUZA does not treat or prevent illness that is caused by infections other than the influenza virus.


XOFLUZA does not prevent bacterial infections that may happen with the flu.


It is not known if XOFLUZA is safe and effective for the treatment and prevention of the flu in children less than 5 years of age. XOFLUZA is not for use in children less than 5 years of age.

Important Safety Information

Who should not take XOFLUZA?

  • Do not take XOFLUZA if you are allergic to baloxavir marboxil or any of the ingredients in XOFLUZA.


What should I tell my healthcare provider before using XOFLUZA?

  • Tell your healthcare provider about all of your medical conditions, including if you are:
    • Pregnant or plan to become pregnant. It is not known if XOFLUZA can harm your unborn baby.
    • Breastfeeding or plan to breastfeed. It is not known if XOFLUZA passes into your breast milk.
  • Talk to your healthcare provider before you receive a live flu vaccine after taking XOFLUZA.
  • Tell your healthcare provider about all of the medicines you take, including prescription and over-the-counter medicines, antacids, laxatives, vitamins, and herbal supplements.

What are the possible side effects of XOFLUZA?
Serious side effects may include

  • Allergic reaction. Get emergency medical help right away if you develop any of the following signs or symptoms of an allergic reaction:
    • trouble breathing
    • skin rash, hives or blisters
    • swelling of your face, throat or mouth
    • dizziness or lightheadedness

The most common side effects of XOFLUZA for treatment of the flu in adults and adolescents (12 years of age and older) were diarrhea, bronchitis, nausea, sinusitis, and headache.


The most common side effects of XOFLUZA for treatment of the flu in children (5 years of age to less than 12 years of age) were diarrhea and vomiting.  


These are not all the possible side effects of XOFLUZA. Call your healthcare provider for medical advice about side effects.

XOFLUZA is not effective in treating or preventing infections other than influenza. Other kinds of infections can have symptoms like those of the flu or occur along with flu and may need different kinds of treatment. Tell your healthcare provider if you feel worse or develop new symptoms during or after treatment with XOFLUZA or if your flu symptoms do not start to get better.

You are encouraged to report side effects to Genentech by calling 1-888-835-2555 or to the FDA by visiting or calling 1-800-FDA-1088.

Please see full Prescribing Information, including Patient Product Information.