Xofluza
Prescription antiviral for acute uncomplicated influenza A and B.What is Xofluza?
Xofluza is a prescription-only medicine in Hong Kong that is widely used for patients presenting with acute uncomplicated influenza.
Unlike neuraminidase inhibitors such as oseltamivir, Xofluza belongs to a class of cap-dependent endonuclease inhibitors that work by stopping the viral replication process within the body.
| Property | Details |
|---|---|
| Medicine Name | Xofluza |
| Also Known As | Baloxavir marboxil |
| What It Does | Manages symptoms of acute uncomplicated influenza A and B. |
| Active Ingredient | Baloxavir marboxil |
| How It Works | Inhibits the cap-dependent endonuclease enzyme to prevent viral replication. |
| How to Take It | Taken orally |
| Forms Available | Tablets, oral suspension |
| Typical Dosage | Adults and children over 5 years: Single oral dose based on body weight. |
| Suitable For | Adults, the elderly, and children aged 5 years or older |
| Not Suitable For | People with severe renal or hepatic impairments, or known allergies to baloxavir marboxil. |
Generic Names:
- Baloxavir marboxil: The universally recognised generic name for the active pharmaceutical ingredient, widely utilised in clinical settings globally.
Global Brand Names:
- Xofluza: This is the primary brand name used internationally, including in Hong Kong, for both adult and paediatric formulations.
What is Xofluza used for?
Xofluza is used to relieve:
- Symptoms associated with acute uncomplicated influenza in otherwise healthy patients, or those at high risk of complications, who have exhibited symptoms for no more than 48 hours.
- The risk of developing symptoms following exposure to an infected individual (post-exposure prophylaxis for patients aged 5 years or above).
How do you use Xofluza?
Availability:
- Oral tablets (Currently the only registered form in Hong Kong).
- Oral suspension.
Suitability:
- Adults: Yes, suitable for general adult use.
- Elderly: Yes, no dose adjustment is required.
- Children: Yes, for those aged 5 years or older.
- Pregnant Women: No, adequate data regarding developmental risks is unavailable.
- Lactating Women: No, due to a lack of data on milk presence and effects on infants.
Dosage Information:
- Patients weighing 20 to <80 kg: 40 mg as a single oral dose.
- Patients weighing 80 kg or more: 80 mg as a single oral dose.
Who cannot take Xofluza?
- Children under 5 years of age.
- Individuals with severe renal impairment.
- Individuals with severe hepatic impairment.
Allergies and unsuitability:
- Rare, but possible severe allergic reactions including anaphylaxis, angioedema, urticaria, and erythema multiforme.
Warnings and precautions:
- Do not rely on this medication for bacterial infections; there is a risk of untreated bacterial complications.
- Monitor for treatment-emergent viral resistance, particularly in younger patients.
Interactions and contraindications:
- Avoid taking with dairy products to maintain drug absorption.
- Avoid coadministration with calcium-fortified beverages or supplements containing polyvalent cations (such as calcium, magnesium, iron, zinc, or selenium) as they can interfere with efficacy.
- Avoid concurrent use with live attenuated influenza vaccine (LAIV) to prevent a decrease in the vaccine's effectiveness.
Conditions where the drug should not be used:
- Known hypersensitivity to baloxavir marboxil.
- Severe renal impairments.
- Severe hepatic impairments.
Common side effects differ slightly by age group. Adults and adolescents may experience diarrhoea, bronchitis, nausea, sinusitis, and headache. Paediatric patients aged 5 to under 12 frequently report vomiting and diarrhoea.
Severe adverse reactions require immediate medical attention. These include serious allergic responses such as difficulty breathing, skin rashes, hives, swelling of the face, throat or mouth, and severe dizziness or lightheadedness. Never exceed the single prescribed dose, as misuse may increase the risk of adverse events.
Warnings and precautions:
- Do not rely on this medication for bacterial infections; there is a risk of untreated bacterial complications.
- Monitor for treatment-emergent viral resistance, particularly in younger patients.
Interactions and contraindications:
- Avoid taking with dairy products to maintain drug absorption.
- Avoid coadministration with calcium-fortified beverages or supplements containing polyvalent cations (such as calcium, magnesium, iron, zinc, or selenium) as they can interfere with efficacy.
- Avoid concurrent use with live attenuated influenza vaccine (LAIV) to prevent a decrease in the vaccine's effectiveness.
Conditions where the drug should not be used:
- Known hypersensitivity to baloxavir marboxil.
- Severe renal impairments.
- Severe hepatic impairments.
Storage information:
- Keep tablets in their original blister package at room temperature.
- Store in a dry place out of reach of children.
Handling instructions:
- Swallow the tablet whole with a glass of water.
- Take the medication as a single dose exactly as prescribed based on your body weight.
Where is Xofluza available in Hong Kong?
Xofluza is classified as a "Prescription Only Medicine" in Hong Kong. Patients must present a valid doctor's prescription to purchase it at a registered pharmacy.
It can be legally obtained at registered dispensaries displaying the "Rx" logo or through hospital and clinic pharmacies directly from a healthcare provider.
How quickly does Xofluza work?
Patients aged 12 years and older typically begin to feel symptom relief in just over two days. It actively starts blocking the virus from multiplying shortly after the single dose is administered.
What happens if I take Xofluza after having symptoms for 48 hours?
The medication may be significantly less effective at reducing the duration of your illness. It is specifically intended for use in patients who have exhibited flu symptoms for no more than 48 hours.
Can I take my dose with food?
Yes, it can be taken with or without food. However, you must avoid taking it at the same time as dairy products or supplements containing calcium, iron, magnesium, selenium, or zinc.
How long does the medication stay in your system?
The active ingredient has a long elimination half-life and remains in your system for several days. This extended duration is the primary reason the treatment only requires a single oral dose to be effective.
What type of medicine is baloxavir marboxil?
It is a prescription antiviral medication used to treat influenza A and B. It works by inhibiting an essential enzyme, which stops the flu virus from replicating within the body.