Oseltamivir: Uses, Side Effects, and How to Take It
Oseltamivir is an antiviral medicine used to treat seasonal influenza A and B and to prevent influenza after exposure. It may shorten the course of illness when started early, but it does not work for colds or other respiratory infections. It is available as capsules and oral suspension.
Oseltamivir can help treat or prevent influenza, but it is not a replacement for vaccination or medical advice. Take it exactly as prescribed, and contact a doctor or pharmacist if you have kidney problems, take other medicines, or have concerning symptoms.
Key facts at a glance
- ATC
- J05AH02
- Generic
- Oseltamivir
- Class
- antiviral
- Brands
- Tamiflu
- Availability
- rx
- Pregnancy
- C
- Lactation
- caution
- Half-life (h)
- 8
- Onset (min)
- 120
- Duration (h)
- 12
- Routes
- oral
- Forms
- capsule, oral-suspension
- Regions
- CN, US, EU, JP
- Monitoring
- neuropsychiatric
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
first trimesteravoid if possible
use only if benefits outweigh potential risks to fetus
regular prenatal monitoring
Use with caution and monitor for adverse effects.
pregnancy
second third trimesterstandard dosing
use when benefits outweigh risks
standard prenatal monitoring
Use with caution and monitor for adverse effects.
lactation
breastfeedingno adjustment needed
compatible with breastfeeding
no specific monitoring required
geriatric
elderly 65 yearsno adjustment needed for normal renal function
standard adult dosing
monitor renal function
pediatric_age
infants 2 weeks to 1 yearweight-based dosing required
use only if benefits outweigh risks
close monitoring for adverse effects
Use with caution and monitor for adverse effects.
pediatric_age
children 1 year and olderweight-based dosing
standard pediatric dosing
standard pediatric monitoring
renal_impairment
severe renal impairmentreduce dose to 75mg once daily for CrCl less than 30mL/min
adjust dose based on renal function
monitor renal function regularly
Use with caution and monitor for adverse effects.
hepatic_impairment
hepatic impairmentno adjustment needed
standard dosing
no specific monitoring required
Statistics and clinical data
FDA approval year
FDA approval for influenza treatment
Drug class
Pharmacological classification
Common uses
Therapeutic indications
Treatment efficacy
Clinical effectiveness data
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 22, 2026. · Read our editorial policy