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Baloxavir marboxil (By mouth)

Baloxavir Marboxil (bal-OX-a-vir mar-BOX-il)

Treats and prevents influenza (flu).

Brand Name(s):

Xofluza, Xofluza 1X40MG (40MG Dose), Xofluza 1X80MG (80MG Dose), Xofluza 2X20MG (40MG Dose), Xofluza 2X40MG (80MG Dose)

When This Medicine Should Not Be Used:

How to Use This Medicine:

Liquid, Tablet

• Your doctor will tell you how much medicine to use. Do not use more than directed. Do not take this medicine for any illness other than the flu.
• Start using this medicine within 48 hours, as soon as the symptoms of flu (including cough, fever, runny nose, headache, joint or muscle pain) appear.
• Take this medicine with or without food. However, do not take this medicine with dairy products or drinks rich in calcium.
• If your child is unable to swallow the tablets whole, you may use the oral liquid.
• Oral liquid:
  • Your pharmacist will prepare the oral liquid. Talk to your pharmacist if it is not given to you as a liquid or if you did not receive a measuring device.
  • Swirl the bottle before each use. Do not shake.
  • Measure the medicine with the provided oral dosing syringe or measuring cup.
  • You should sit upright when taking this medicine. Do not mix it with soft food or another liquid.
  • If it is given through a feeding tube: Using a syringe, rinse the feeding tube with 1 milliliter (mL) of water. Then, inject the oral syringe with medicine into the feeding tube and rinse the tube with 1 mL water.
• Take all of the medicine in your prescription to clear up your infection, even if you feel better after the first few doses.
• Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.
• Missed dose: Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.
• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
• Throw away any unused liquid within 10 hours of mixing.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Do not use this medicine together with antacids, laxatives, or oral supplements containing calcium, iron, magnesium, selenium, or zinc.
• Do not use this medicine if you have received the nasal flu vaccine (live attenuated influenza vaccine), unless your doctor says it is okay.

Warnings While Using This Medicine:

• Tell your doctor if you are pregnant or breastfeeding, or if you have any type of infection.
• This medicine is not a substitute for a yearly flu shot. It also will not treat or prevent a bacterial infection.
• Call your doctor if your symptoms do not improve or if they get worse.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Blistering, peeling, or loosening of the skin
• Chest tightness, trouble breathing
• Fever, chills, cough, sore throat, body aches
• Headache, pain or tenderness around your eyes and cheekbones

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 3/6/2023