Oseltamivir

Antiviral, Systemic · Neuraminidase inhibitor

Indications

Treatment and prevention of influenza when the virus is in the community.

Dosage

Adults: Treatment: 75 mg twice daily for 5 days starting within 2 days of onset of symptoms. Prevention: 75 mg once daily starting within 2 days of exposure to an infected individual and continued for 10 days or up to 6 wk during an epidemic. Children: Treatment: Under 1 yr, not recommended. 1-12 yr, under 15 kg: 30 mg; 15-23 kg: 45 mg; 23-40 kg: 60 mg; over 40 kg: 75 mg. All twice daily for 5 days. Prevention: Under 1 yr, not recommended. 1-12 yr, under 15 kg: 30 mg; 15-23 kg: 45 mg; 23-40 kg: 60 mg; over 40 kg: 75 mg. All once daily for 10 days or up to 6 wk during an epidemic.

Adverse Effects

GI upset, respiratory infection, dizziness, fatigue, headache, insomnia, vertigo, cough, rhinorrhoea, pain.

Risk Factor (Pregnancy/Lactation)

Pregnancy: Risk cannot be ruled out. Lactation: Caution advised or effect undetermined. Contraindications: Renal impairment. Precautions: Severe renal impairment (CrCl 11-60 mL/min), dialysis. Risk of neuropsychiatric events; monitor closely for behavioural changes. Immunocompromised patients. Premature infants.

Interactions

Chlorpropamide, methotrexate, phenylbutazone.

Advice to Patient

Take with or without meals. To reduce abdominal discomfort, take with meals. To enhance flavour, open capsule and mix contents into sweetened condensed milk, chocolate syrup, yoghurt or applesauce then swallow mixture immediately. Take this medication within 2 days of flu symptoms such as headache, cough, fever, muscular weakness, fatigue, sore throat. Contact prescriber if significant side effects occur.

Pharmacokinetics

Absorption: Well absorbed. Metabolism: Hepatic (90%) to oseltamivir carboxylate. Bioavailability: 75% as oseltamivir carboxylate. Half-life elimination: Oseltamivir: 1-3 hrs. Oseltamivir carboxylate: 6-10 hrs. Excretion: Urine (>99%). Faeces (<20%).

Brands with this active ingredient

Compiled by Healify Pharmacy from published drug references. How we compile it →

Always consult a pharmacist or doctor.