Oseltamivir oral
- Drugs List
- Therapeutic Indications
- Dosage
- Administration
- Contraindications
- Precautions and Warnings
- Pregnancy and Lactation
- Side Effects
- Monograph
Presentation
Oral formulations containing oseltamivir as oseltamivir phosphate.
Drugs List
Therapeutic Indications
Uses
Influenza - prophylaxis
Influenza - treatment of symptoms
Dosage
The use of antivirals for the treatment and prevention of influenza should be determined on the basis of official recommendations. Decisions regarding the use of oseltamivir for treatment and prophylaxis should take into consideration what is known about the characteristics of the circulating influenza viruses, available information on influenza drug susceptibility patterns for each season and the impact of the disease in different geographical areas and patient populations.
Licensed oseltamivir suspension and capsules are bioequivalent formulations.
Unlicensed, special order, oral liquids may be available in different concentrations. Exercise care when determining dose in millilitres.
Adults
Treatment of influenza
75mg oseltamivir twice daily for five days.
Immunocompromised: 75mg oseltamivir twice daily for ten days.
Treatment should be started within two days of the onset of symptoms.
Post-exposure prevention
75mg oseltamivir once daily for ten days.
Therapy should begin as soon as possible within two days of exposure to an infected individual.
Prevention during an influenza epidemic in the community
75mg oseltamivir once daily for up to six weeks.
Immunocompromised: 75mg oseltamivir once daily for up to twelve weeks.
Children
Children aged 13 years and older
(See Dosage; Adults)
Children aged 1 to 12 years
Treatment of influenza
Treatment should be started within two days of the onset of symptoms and continued for five days, or for ten days in immunocompromised patients.
Bodyweight greater than 40kg: 75mg twice daily.
Bodyweight greater than 23kg to 40kg: 60mg twice daily.
Bodyweight greater than 15kg to 23kg: 45mg twice daily.
Bodyweight 10kg to 15kg: 30mg twice daily.
Post-exposure prevention
Treat for ten days according to bodyweight.
Bodyweight greater than 40kg: 75mg once daily.
Bodyweight greater than 23kg to 40kg: 60mg once daily.
Bodyweight greater than 15kg to 23kg: 45mg once daily.
Body weight 10kg to 15kg: 30mg once daily.
Prevention during an influenza epidemic in the community
Treat for up to 6 weeks, or up to 12 weeks if the patient is immunocompromised.
Bodyweight greater than 40kg: 75mg once daily.
Bodyweight greater than 23kg to 40kg: 60mg once daily.
Bodyweight greater than 15kg to 23kg: 45mg once daily.
Body weight 10kg to 15kg: 30mg once daily.
Children aged 0 to 12 months
The doses suggested below are not intended for premature infants (post conceptual age less than thirty six weeks).
Treatment of influenza
3mg per kg bodyweight twice daily for five days, or for ten days in immunocompromised patients.
The following weight adjusted dosing regimens are recommended for treatment of infants below 1 year of age:
Bodyweight greater than 9kg to 10kg: 30mg twice daily.
Bodyweight greater than 8kg to 9kg: 27mg twice daily.
Bodyweight greater than 7kg to 8kg: 24mg twice daily.
Bodyweight greater than 6kg to 7kg: 21mg twice daily.
Bodyweight 6kg: 18mg twice daily.
Bodyweight 5.5kg: 16.5mg twice daily.
Bodyweight 5kg: 15mg twice daily.
Bodyweight 4.5kg: 13.5mg twice daily.
Bodyweight 4kg: 12mg twice daily.
Bodyweight 3.5kg: 10.5mg twice daily.
Bodyweight 3kg: 9mg twice daily.
Post-exposure prevention
Recommended prophylaxis dose for infants less than twelve months during a pandemic influenza outbreak is half of the daily treatment dose.
3mg per kg bodyweight once daily for ten days.
The following weight adjusted dosing regimens are recommended for infants below 1 year of age:
Bodyweight greater than 9kg to 10kg: 30mg once daily.
Bodyweight greater than 8kg to 9kg: 27mg once daily.
Bodyweight greater than 7kg to 8kg: 24mg once daily.
Bodyweight greater than 6kg to 7kg: 21mg once daily.
Bodyweight 6kg: 18mg once daily.
Bodyweight 5.5kg: 16.5mg once daily.
Bodyweight 5kg: 15mg once daily.
Bodyweight 4.5kg: 13.5mg once daily.
Bodyweight 4kg: 12mg once daily.
Bodyweight 3.5kg: 10.5mg once daily.
Bodyweight 3kg: 9mg once daily.
Prevention during an influenza epidemic in the community
Prevention during an influenza epidemic has not been studied in this age group.
Patients with Renal Impairment
Treatment of influenza in adults and adolescents (aged 13 years and older)
Creatinine clearance greater than 60ml/minute: 75mg twice daily.
Creatinine clearance 31 to 60ml/minute: 30mg twice daily.
Creatinine clearance 11 to 30ml/minute: 30mg once daily.
Creatinine clearance equal to or less than 10ml/minute: Not recommended.
Dialysis patients
Haemodialysis patient: 30mg after each haemodialysis session.
Peritoneal dialysis patient: 30mg as a single dose.
Prevention of influenza in adults and adolescents (aged 13 years and older)
Creatinine clearance greater than 60ml/minute: 75mg once daily.
Creatinine clearance 31 to 60ml/minute: 30mg once daily.
Creatinine clearance 11 to 30ml/minute: 30mg every second day.
Creatinine clearance equal to or less than 10ml/minute: Not recommended.
Dialysis patient
Haemodialysis patient: 30mg after every second haemodialysis session
Peritoneal dialysis patient: 30mg once a week
For children with renal impairment, insufficient data are available to determine dosing requirements.
The following unlicensed dosing schedule may be suitable:
Treatment of influenza in children:
Estimated glomerular filtration rate 30 to 60ml/minute/1.73 metre squared: 40% of normal dose twice daily.
Estimated glomerular filtration rate 10 to 30 ml/minute/1.73 metre squared: 40% of normal dose once daily.
Prevention of influenza in children:
Estimated glomerular filtration rate 30 to 60 ml/minute/1.73 metre squared: 40% of normal dose once daily.
Estimated glomerular filtration rate 10 to 30 ml/minute/1.73 metre squared: 40% of normal dose every 48 hours.
Administration
In areas where commercially manufactured oseltamivir oral suspension is not readily available, patients unable to swallow capsules may receive appropriate doses of oseltamivir by opening the capsules and pouring the contents into a suitable amount (maximum 1 teaspoon) of sweetened food product to mask the bitter taste. The mixture should be stirred and the entire contents given to the patient. The mixture must be swallowed immediately after preparation.
Contraindications
Premature infants
Within 2 weeks of administration of live influenza virus vaccine
Renal impairment - creatinine clearance below 10ml/minute
Precautions and Warnings
Children under 1 year
Immunosuppression
Breastfeeding
Hereditary fructose intolerance
Immunodeficiency syndromes
Pregnancy
Renal dialysis
Renal impairment - creatinine clearance below 60ml/minute
Renal impairment in children under 18 years
Additional doses may be required in immunosuppressed patients
Reduce dose in patients with creatinine clearance below 60ml/min
Not a substitute for annual influenza vaccination in at-risk patients
Not all presentations are licensed for all indications
May contain sodium benzoate: may increase risk of jaundice in neonates
Presentations with sorbitol unsuitable in hereditary fructose intolerance
Monitor patients for behavioural changes
The use of oseltamivir must not affect annual influenza vaccination schedules. Protection against influenza only lasts as long as oseltamivir is administered.
Oseltamivir should only be used when reliable epidemiological data indicates that the influenza virus is circulating in the community. Susceptibility of circulating influenza virus strains to oseltamivir has been shown to be highly variable. When deciding whether to use oseltamivir, prescribers should take into account the most recent information available on oseltamivir susceptibility patterns of the currently circulating viruses.
Pregnancy and Lactation
Pregnancy
Use oseltamivir with caution in pregnancy.
Due to the high risk of harm from influenza infection, oseltamivir may be used with caution in pregnancy, provided the expected maternal benefit outweighs the potential foetal harm. The manufacturer suggests that pregnant women may receive oseltamivir only after considering the available safety information, the pathogenicity of the circulating influenza virus strain and the underlying condition of the pregnant woman.
The majority of available information from post-marketing and observational studies indicate that oseltamivir use in pregnancy does not increase the overall risk of malformation in the foetus. One observational study highlighted a slightly elevated risk of major congenital heart defects following use of oseltamivir in the first trimester.
Studies in animals did not indicate reproductive toxicity.
Lactation
Use oseltamivir with caution in breastfeeding.
Limited data indicates that oseltamivir and its active metabolite are excreted into human breast milk in small amounts. The manufacturer states that due to the high risk of harm from influenza infection, oseltamivir may be used with caution in breast feeding.
LactMed concludes that maternal doses of up to 150mg daily would result in only small amounts of oseltamivir in breast milk, and would not be expected to cause adverse effects in the breastfed infant.
Side Effects
Abdominal pain
Agitation
Altered consciousness
Anaphylactic reaction
Anaphylactoid reaction
Angioneurotic oedema
Anxiety
Arrhythmias
Behavioural disturbances
Bronchitis
Confusion
Conjunctivitis
Convulsions
Cough
Delirium
Delusions
Dermatitis
Dizziness
Dyspepsia
Ear pain
Eczema
Erythema multiforme
Fatigue
Fulminant hepatitis
Gastrointestinal bleeding
Haemorrhagic colitis
Hallucinations
Headache
Hepatic disorders
Hepatic failure
Hepatic impairment
Hepatitis
Herpes simplex
Hypersensitivity reactions
Increases in hepatic enzymes
Inflicted injury
Insomnia
Jaundice
Limb pain
Nasal congestion
Nasopharyngitis
Nausea
Nightmares
Otitis media
Pain
Pyrexia
Rash
Rhinorrhoea
Sinusitis
Sore throat
Stevens-Johnson syndrome
Thrombocytopenia
Toxic epidermal necrolysis
Tympanic membrane disorder
Upper respiratory tract infection
Urticaria
Vertigo
Visual disturbances
Vomiting
Overdosage
It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.
The following number will direct the caller to the relevant local centre (0844) 892 0111
Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( www.toxbase.org ) or if this is unavailable at the backup site ( www.toxbasebackup.org ).
Further Information
Last Full Review Date: March 2013
Reference Sources
Summary of Product Characteristics: Ebilfumin 30mg, 45mg & 75mg hard capsules. Teva UK Ltd. Revised February 2019.
Summary of Product Characteristics: Tamiflu 30mg, 45mg & 75mg Hard Capsules. Roche Products Ltd. Revised February 2019.
Summary of Product Characteristics: Tamiflu 6mg/ml powder for oral suspension. Roche Products Ltd. Revised August 2020.
NHS Direct Medicines Fact Sheet, Tamiflu (oseltamivir) Version 4.3, Produced by NHS Direct UKMI Working Group.
https://www.nelm.nhs.uk/en/NeLM-Area/Evidence/Medicines-Q--A/What-information-is-NHS-Direct-giving-patients-about-oseltamivir-Tamiflu/
Last updated: December 3, 2010
Last accessed: March 07, 2013
NICE Evidence Services Available at: www.nice.org.uk Last accessed: 04 April 2019
US National Library of Medicine. Toxicology Data Network. Drugs and Lactation Database (LactMed).
Available at: https://toxnet.nlm.nih.gov/cgi-bin/sis/htmlgen?LACT
Oseltamivir Last revised: 10 March 2015
Last accessed: 8th June 2018
Medscape UK | Univadis prescription drug monographs & interactions are based on FDB Multilex Content
FDB Disclaimer : FDB Multilex is intended for the use of healthcare professionals and is provided on the basis that the healthcare professionals will retain FULL and SOLE responsibility for deciding what treatment to prescribe or dispense for any particular patient or circumstance.