OSELTAMIVIR PHOSPHATE

Antiviral medicine, Neuraminidase Inhibitors. Reduces replication of influenza A and B viruses by inhibition of viral neuraminidase

Dosage Forms

Tablet

75 mg

Uses

  • Treatment of avian influenza type A H5N1
  • Prevention of avian influenza type A H5N1

Dose and Duration

Treatment of avian influenza type A H5N1

Adult and child >13 years: 75 mg every 12 hours for 5 days

Child 1–13 years: give as below every 12 hours for 5 days

Body weight (kg) Dose every 12 hours
>40 75 mg
23–40 60 mg
15–23 45mg
10–15 30mg

Child 3–12 months: 3 mg/kg every 12 hours for 5 days

Child 1–3 months: 2.5 mg/kg every 12 hours for 5 days

Neonate: 2 mg/kg every 12 hours for 5 days

Renal impairment: eGFR 30–60 ml/minute/1.73 m², 30 mg every 12 hours; eGFR 10–30 ml/minute/1.73 m², 30 mg once daily

Prevention of avian influenza type A H5N1

Give for 10 days in post exposure prophylaxis (PEP) or for up to 6 weeks in an epidemic.

Adult and child over 13 years: 75 mg every 24 hours

Child 1–13 years: as in table below

Body weight (kg) Dose every 12 hours
>40 75 mg
23–40 60 mg
15–23 45mg
10–15 30mg

Child 3–12 months: 3 mg/kg every 24 hours for 10 days

Child 1–3 months: 2.5 mg/kg every 24 hours for 10 days

Neonate: 2 mg/kg every 24 hours for 10 days

Renal impairment: eGFR 30–60 ml/minute/1.73 m², 30 mg once daily; eGFR 10–30 ml/minute/1.73 m², 30 mg every 48 hours

Contraindications

  • Hypersensitivity to oseltamivir

Side Effects

  • Nausea, vomiting, abdominal pain, dyspepsia
  • Cough, sore throat, rhinorrhoea, bronchitis, upper respiratory tract infections
  • Insomnia, headache
  • Herpes simplex
  • Pain, fatigue, dizziness, pyrexia
  • Anaphylactic reactions
  • Hepatic failure
  • Stevens-Johnson syndrome

Pregnancy

  • Can be used

Breast-feeding

  • Can be used

⚠️ Caution

  • Do not use in renal failure if eGFR is >10 ml/minute/m²
  • Give within 48 hours of exposure
  • May be ineffective in neonates since they may be unable to metabolise it to its active form. Use under supervision
  • Only use in pregnancy and breast-feeding if benefit outweighs risk