For Patients and Caregivers

About the Flu

Recognize and Treat the Flu Promptly With an Antiviral1*

There are serious risks associated with the flu2,3

Most patients who get the flu recover in 3 to 14 days, but influenza can cause complications that could be life threatening. For high-risk patients, dangers of the flu are even greater and can lead to serious complications, make chronic health problems worse, or even cause death.
 

During the 2025 to 2026 flu season in the United States, the CDC estimated that influenza was associated with up to4:

32-57 MILLION
FLU ILLNESSES

390,000-800,000
HOSPITALIZATIONS

24,000-81,000
DEATHS

Flu vaccines are widely available and play an essential role in flu prevention; however, they are not always used or may not always be effective, leaving people at risk.5

Treat the Flu Immediately

Icon of a prescription. Treat the flu with XOFLUZA

The flu is a serious, contagious disease that impacts people of all ages and ethnicities. To make matters more serious, some symptoms of the flu can be quite similar to and/or overlap with the typical symptoms of COVID-19 and the common cold.6,7

Signs and Symptoms6-8 Flu6-8 COVID-196-8 Common Cold6-8
Incubation Period 1-4 days Varies Varies, but usually
under 2 days
Symptom onset Sudden Varies Gradual
Fever Common Common Rare
Chills Common Common Uncommon
Cough Common Common Common
Fatigue Common Common Sometimes
Sneezing Sometimes Rare Common
Nasal Congestion/​​​Stuffy and/or Runny Nose Sometimes Common Common
New Loss of Taste/​Sense of Smell Rare Common Common
Diarrhea Common Common Rare
Body Aches Common Common Slight
Sore Throat Sometimes Common Common
Headache Common Common Rare
Shortness of Breath Common Common Not Reported/​Rare

Although a single-dose of XOFLUZA does not treat COVID-19 or the common cold, coinfection with the flu and COVID-19 is possible. If the flu is confirmed or suspected, consider prescribing a flu antiviral immediately, regardless of COVID-19 infection.1,6

Influenza antivirals have been shown to shorten the duration of flu symptoms.9

The CDC Recommends Treating the Flu Empirically With an Antiviral9

When there is a clinical diagnosis of flu or suspected flu, the CDC recommends treating flu patients at high risk of developing complications empirically with an antiviral flu treatment. Empiric antiviral treatment is also recommended for non–high-risk outpatients with suspected influenza based on clinical judgment, including without an office visit, in communities where influenza is circulating. The CDC has included XOFLUZA among its list of antiviral medications recommended for the flu.†

Treating with single-dose XOFLUZA promptly (within 48 hours of symptom onset) can help alleviate flu symptoms in appropriate patients.1

†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 CDC.gov.

Icon of virus. Reduce their risk of contracting the flu after exposure by taking single-dose XOFLUZA
Act After Exposure

Patients can reduce their risk of contracting the flu after exposure to an infected household member by taking single-dose XOFLUZA.1

Post-exposure prophylaxis efficacy

Frequently
asked
questions

XOFLUZA (baloxavir marboxil) is an oral influenza antiviral. It is an influenza virus polymerase acidic (PA) endonuclease inhibitor: a prodrug that converts to baloxavir, which inhibits the PA endonuclease, an influenza virus–specific enzyme required for viral gene transcription, thereby inhibiting influenza virus replication.1

XOFLUZA is taken as a single, weight-based oral dose. Please refer to the XOFLUZA Prescribing Information for the most current FDA-approved indications.1

Potential candidates include patients 5 years of age and older with acute uncomplicated influenza whose symptoms began within the 48-hour treatment window, including otherwise healthy patients and patients at high risk for influenza-related complications. It is also indicated for post-exposure prophylaxis of influenza in patients 5 years of age and older following contact with an individual who has influenza.1

Treatment decisions should consider clinical presentation, timing from symptom onset, influenza activity, patient-specific risk factors, and guidance from the Centers for Disease Control and Prevention (CDC) or local public health authorities. XOFLUZA is not a substitute for annual influenza vaccination.

Please refer to the Xofluza Prescribing Information for the most current FDA-approved indications.

For treatment, XOFLUZA should be initiated as soon as possible and within 48 hours of influenza symptom onset, per the US label.1

Patients should be managed according to current clinical guidelines and institutional protocols.

Yes. In the US, XOFLUZA is indicated for post-exposure prophylaxis of influenza in patients 5 years of age and older following contact with an individual who has influenza.1

Post-exposure prophylaxis decisions should consider exposure history, timing, patient-specific risk factors, and current CDC or local public health guidance. Xofluza is not a substitute for annual influenza vaccination.

Yes. XOFLUZA is approved for the treatment of acute uncomplicated influenza in patients 5 years of age and older who have been symptomatic for no more than 48 hours. Clinical studies of XOFLUZA for the treatment of influenza included patients with influenza A (predominantly A/H1N1 and A/H3N2) and influenza B.1

Treatment decisions should weigh the potential benefits and risks, disease severity, and patient risk factors, together with the current Prescribing Information and guidance from the Centers for Disease Control and Prevention (CDC) or local public health authorities.

IMPORTANT SAFETY INFORMATION & INDICATION

Indication

XOFLUZA is an influenza virus polymerase acidic (PA) endonuclease inhibitor indicated for:

  • Treatment of acute uncomplicated influenza in patients 5 years of age and older who have been symptomatic for no more than 48 hours and who are otherwise healthy or at high risk of developing influenza-related complications.
  • Post-exposure prophylaxis (PEP) of influenza in patients 5 years of age and older following contact with an individual who has influenza.

Limitations of Use
Influenza viruses change over time, and factors such as the virus type or subtype, emergence of resistance, or changes in viral virulence could diminish the clinical benefit of antiviral drugs. Consider available information on drug susceptibility patterns for circulating influenza virus strains when deciding whether to use XOFLUZA.

Important Safety Information

Contraindications
XOFLUZA is contraindicated in patients with a history of hypersensitivity to baloxavir marboxil or any of its ingredients. Serious allergic reactions have included anaphylaxis, angioedema, urticaria, and erythema multiforme.

Warnings and Precautions

Hypersensitivity: Cases of anaphylaxis, urticaria, angioedema, and erythema multiforme have been reported in postmarketing experience with XOFLUZA. Appropriate treatment should be instituted if an allergic-like reaction occurs or is suspected.

Increased Incidence of Treatment-Emergent Resistance in Patients Less Than 5 Years of Age: XOFLUZA is not indicated in patients less than 5 years of age due to increased incidence of treatment-emergent resistance in this age group. In clinical trials, the incidence of virus with treatment-emergent substitutions associated with reduced susceptibility to baloxavir (resistance) was higher in pediatric subjects younger than 5 years of age (40%, 38/96) than in pediatric subjects ≥5 years to <12 years of age (16%, 19/117) or subjects ≥12 years of age (7%, 60/842). The potential for transmission of resistant strains in the community has not been determined.

Risk of bacterial infections: There is no evidence of the efficacy of XOFLUZA in any illness caused by pathogens other than influenza viruses. Serious bacterial infections may begin with influenza-like symptoms or may coexist with, or occur as, a complication of influenza. XOFLUZA has not been shown to prevent such complications. Prescribers should be alert to potential secondary bacterial infections and treat them as appropriate.

Adverse Reactions

  • The most common adverse reactions (≥1%) in adult and adolescent patients (≥12 years of age) in clinical studies for acute uncomplicated influenza were diarrhea (3%), bronchitis (3%), nausea (2%), sinusitis (2%), and headache (1%).
  • The most frequently reported adverse reactions (≥5%) in pediatric patients (5 to <12 years of age) in clinical studies for acute uncomplicated influenza were vomiting (5%) and diarrhea (5%).
  • The safety profile reported in a clinical study for post-exposure prophylaxis was similar in pediatric patients ages 5 to <12 years old as that reported in adults and adolescents 12 years of age and older.

Drug Interactions
Polyvalent cations: Coadministration with polyvalent cation-containing products may decrease plasma concentrations of baloxavir, which may reduce XOFLUZA efficacy. Avoid coadministration of XOFLUZA with dairy products, calcium-fortified beverages, polyvalent cation-containing laxatives, antacids, or oral supplements (eg, calcium, iron, magnesium, selenium, or zinc).

Vaccines: The concurrent use of XOFLUZA with intranasal live attenuated influenza vaccine (LAIV) has not been evaluated. Concurrent administration of antiviral drugs may inhibit viral replication of LAIV and, thereby, decrease the effectiveness of LAIV vaccination. Interactions between inactivated influenza vaccines and XOFLUZA have not been evaluated.

For additional Important Safety Information, please see the XOFLUZA full Prescribing Information.

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

    • XOFLUZA. Prescribing information. Genentech, Inc.

      XOFLUZA. Prescribing information. Genentech, Inc.

    • Incalzi RA, Consoli A, Lopalco P, et al. Influenza vaccination for elderly, vulnerable and high-risk subjects: a narrative review and expert opinion. Intern Emerg Med. 2024;19(3):619-640. doi:10.1007/s11739-023-03456-9

      Incalzi RA, Consoli A, Lopalco P, et al. Influenza vaccination for elderly, vulnerable and high-risk subjects: a narrative review and expert opinion. Intern Emerg Med. 2024;19(3):619-640. doi:10.1007/s11739-023-03456-9

    • Clinical signs and symptoms of influenza. Centers for Disease Control and Prevention. Last reviewed February 4, 2026. Accessed August 18, 2026. https://www.cdc.gov/flu/hcp/clinical-signs/index.html

      Clinical signs and symptoms of influenza. Centers for Disease Control and Prevention. Last reviewed February 4, 2026. Accessed August 18, 2026. https://www.cdc.gov/flu/hcp/clinical-signs/index.html

    • Preliminary estimated flu disease burden 2025-2026 flu season. Centers for Disease Control and Prevention. Last reviewed November 21, 2025. Accessed August 18, 2026. https://www.cdc.gov/flu-burden/php/php/data-vis/2025-2026.html

      Preliminary estimated flu disease burden 2025-2026 flu season. Centers for Disease Control and Prevention. Last reviewed November 21, 2025. Accessed August 18, 2026. https://www.cdc.gov/flu-burden/php/php/data-vis/2025-2026.html

    • Preventing seasonal flu. Centers for Disease Control and Prevention. Last reviewed September 26, 2025. Accessed August 18, 2026. https://www.cdc.gov/flu/prevention/

      Preventing seasonal flu. Centers for Disease Control and Prevention. Last reviewed September 26, 2025. Accessed August 18, 2026. https://www.cdc.gov/flu/prevention/

    • Is it flu, COVID-19 allergies or a cold? National Institutes of Health. Last reviewed January 2022. Accessed August 18, 2026. https://newsinhealth.nih.gov/2022/01/it-flu-covid19-allergies-or-cold

      Is it flu, COVID-19 allergies or a cold? National Institutes of Health. Last reviewed January 2022. Accessed August 18, 2026. https://newsinhealth.nih.gov/2022/01/it-flu-covid19-allergies-or-cold

    • Is it a cold, the flu, or COVID-19? National Institute on Aging. Last reviewed June 5, 2025. Accessed August 18, 2026. https://www.nia.nih.gov/health/covid-19/it-cold-flu-or-covid-19

      Is it a cold, the flu, or COVID-19? National Institute on Aging. Last reviewed June 5, 2025. Accessed August 18, 2026. https://www.nia.nih.gov/health/covid-19/it-cold-flu-or-covid-19

    • COVID-19 Treatment Guidelines Panel. Coronavirus Disease 2019 (COVID-19) Treatment Guidelines. National Institutes of Health. Updated February 29, 2024. Accessed August 18, 2026. https://www.ncbi.nlm.nih.gov/books/​NBK570371/pdf/​Bookshelf_NBK570371.pdf

      COVID-19 Treatment Guidelines Panel. Coronavirus Disease 2019 (COVID-19) Treatment Guidelines. National Institutes of Health. Updated February 29, 2024. Accessed August 18, 2026. https://www.ncbi.nlm.nih.gov/books/​NBK570371/pdf/​Bookshelf_NBK570371.pdf

    • Influenza antiviral medications: summary for clinicians. Centers for Disease Control and Prevention. Last reviewed March 10, 2026. Accessed August 21, 2026. https://www.cdc.gov/​flu/​professionals/​antivirals/​summary-clinicians.html

      Influenza antiviral medications: summary for clinicians. Centers for Disease Control and Prevention. Last reviewed March 10, 2026. Accessed August 21, 2026. https://www.cdc.gov/​flu/​professionals/​antivirals/​summary-clinicians.html

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