Like all medicines, this medicine can cause side effects, although not everybody gets them. Many of the side effects listed below may also be caused by influenza. The following serious side effects have been rarely reported since oseltamivir has been marketed:

• Anaphylactic and anaphylactoid reactions: severe allergic reactions, with face and skin swelling, itchy rashes, low blood pressure and breathing difficulties.
• Hepatic disorders (fulminant hepatitis, hepatic function disorder and jaundice): yellowing of the skin and whites of the eyes, change in stool colour, and changes in behaviour.
• Angioneurotic oedema: sudden onset of severe swelling of the skin, mainly around the head and neck area (including eyes and tongue), with difficulties breathing.
• Stevens–Johnson syndrome and toxic epidermal necrolysis: complicated, possibly life-threatening allergic reactions causing severe inflammation of the outer and possibly inner skin, initially with fever, sore throat and fatigue, followed by rashes, blisters, peeling and shedding of skin, possible breathing difficulties and low blood pressure.
• Gastrointestinal bleeding: prolonged bleeding from the large bowel or spitting up blood.
• Neuropsychiatric disorders: behavioural changes or abnormal mental states have been reported, mainly in children and adolescents.

Always read the patient information leaflet before commencing treatment.

• To treat a current outbreak: The recommended oral dose is one tablet of Tamiflu (75mg) twice daily for 5 days.
• To prevent catching the flu from someone who is infected: The recommended dose for prevention of influenza following close contact with an infected individual is one tablet (75mg) daily for 10 days.
• Seasonal Protection: The recommended dose for prevention of influenza during a community outbreak is Tamiflu (75mg) once daily for up to 6 weeks.