Fluvir 75 mg (Oseltamivir): Complete Guide to Influenza Treatment & Prevention

✅ What is Fluvir 75 mg Used For?

Fluvir 75 mg (Oseltamivir) is an antiviral medication primarily used for the treatment and prevention of influenza (flu). It works by inhibiting the enzyme neuraminidase, which is crucial for the influenza virus to replicate and spread in the body.

Indications:

1. Treatment of Influenza:
   1. Fluvir is used to treat acute uncomplicated influenza in patients who have had symptoms for no more than 48 hours. It is effective against both influenza A and influenza B viruses.
2. Prevention of Influenza:
   1. It is also used to prevent influenza in individuals who have been exposed to the virus, especially in those who are at high risk for complications, such as the elderly, young children, and immunocompromised individuals.

⚙️ Mechanism of Action

Fluvir (Oseltamivir) inhibits the enzyme neuraminidase, which is located on the surface of the influenza virus. This enzyme is responsible for cleaving sialic acid residues on host cell membranes, allowing the virus to release new viral particles from infected cells.

By blocking neuraminidase, Fluvir prevents the virus from spreading to other cells in the body, thereby reducing the severity and duration of flu symptoms and decreasing the likelihood of complications.

💊 Dosage and Administration

Recommended Dose:

For Treatment of Influenza:

• Adults and Children (13 years and older):
  • The usual dose is 75 mg twice a day for 5 days.
• Children (1 year and older):
  • Dosage is based on body weight. For children over 40 kg, the adult dose of 75 mg twice a day is used.

For Prophylaxis (Prevention) of Influenza:

• Adults and Children (13 years and older):
  • 75 mg once a day for up to 10 days after exposure to influenza.
• Children (1 year and older):
  • 75 mg once a day for up to 10 days, depending on the exposure risk and weight.

⚠️ Warnings and Precautions

1. Risk of Neuropsychiatric Events:

• Fluvir has been associated with neuropsychiatric events such as confusion, delirium, hallucinations, and unusual behavior. These effects are more commonly observed in children and adolescents.
• Monitor for changes in behavior, especially in young patients, and report any unusual symptoms immediately.

2. Renal Impairment:

• Oseltamivir is excreted through the kidneys, so patients with impaired renal function may require dose modifications.
• Monitor kidney function in patients with pre-existing renal conditions.

3. Not a Substitute for Vaccination:

• Fluvir is not a substitute for the annual flu vaccine. Vaccination remains the best method of flu prevention.
• Fluvir is used only after exposure to or infection with the influenza virus.

4. Use with Caution in Pregnant and Breastfeeding Women:

• While Fluvir is classified as Category C for pregnancy (meaning it may be harmful, but the benefits may outweigh the risks in certain cases), it should only be used during pregnancy if clearly needed.
• Breastfeeding mothers should also consult a healthcare provider, as oseltamivir is excreted in breast milk.

❌ Contraindications

• Hypersensitivity: Do not use Fluvir in patients who have had a previous allergic reaction to oseltamivir or any of its components.
• Severe Renal Impairment: Patients with severe kidney dysfunction may require dose adjustments and should use Fluvir with caution.

🔄 Drug Interactions

Fluvir (Oseltamivir) has few significant drug interactions, but it may interact with:

1. Probenecid: This drug can increase the levels of oseltamivir in the bloodstream, potentially increasing the risk of side effects.
2. Live Attenuated Influenza Vaccine (LAIV): If a patient is receiving the LAIV vaccine, they should avoid Fluvir as it may reduce the effectiveness of the vaccine.

Always inform your doctor of any other medications you are taking, including over-the-counter products.

📊 Clinical Efficacy

Effectiveness in Treating Influenza:

• Fluvir (Oseltamivir) is most effective when taken within 48 hours of the onset of flu symptoms.
• It has been shown to reduce the duration of flu symptoms by approximately 1-2 days.
• It can also reduce the risk of complications (such as pneumonia) and hospitalization in certain high-risk populations.

Effectiveness in Prevention:

• When taken after exposure to influenza, Fluvir can reduce the likelihood of developing the flu by about 70-90%.

📋 Side Effects

Common Side Effects:

• Nausea
• Vomiting
• Diarrhea
• Headache
• Fatigue
• Dizziness

Serious Side Effects:

• Neuropsychiatric events (e.g., confusion, hallucinations, delirium)
• Severe allergic reactions (e.g., anaphylaxis)
• Renal impairment or changes in kidney function

Rare Side Effects:

• Rash
• Hepatic dysfunction
• Hemorrhagic complications

🧊 Storage Instructions

• Store at room temperature (15°C to 30°C / 59°F to 86°F).
• Keep in the original packaging to protect from moisture.
• Keep out of reach of children.
• If you are pregnant or breastfeeding, discuss with your doctor whether Fluvir is appropriate for you.
• Fluvir is not a substitute for the flu vaccine.