Tamiflu (oseltamivir) is usually taken once or twice daily for a short time, depending on whether it is for treating the flu or preventing it after exposure. Always follow the exact schedule your own doctor prescribes, since age, kidney function, and reason for use all matter.

Typical schedules

  • For flu treatment in most teens and adults: 75 mg twice a day for 5 days , about 12 hours apart. Starting within 48 hours of symptom onset helps it work best.
  • For flu prevention after close contact exposure: 75 mg once a day for at least 10 days. In community outbreaks, prevention courses can last up to 6–12 weeks if a clinician recommends it.

How often for children

Children’s Tamiflu doses are based on age and weight , and may be liquid or capsules. Kids usually take it twice daily for 5 days for treatment and once daily for 10 days for prevention, but exact milligram amounts differ by weight band.

Timing and practical tips

  • Try to take it at the same times each day (for example, 8 am and 8 pm for twice‑daily dosing) to keep levels steady in the body.
  • It can be taken with or without food, but taking it with food may reduce nausea or stomach upset.
  • If a dose is missed, usual advice is not to double up, but to ask a pharmacist or doctor what to do based on how close it is to the next dose.

Important safety notes

  • People with kidney problems often need a reduced dose or less frequent schedule, so they must use a personalized plan from their clinician.
  • Stop and seek urgent medical help for serious allergic reactions, hallucinations, confusion, or very unusual behavior, especially in children or teens.
  • Tamiflu is a prescription drug, so how often you should take it must be decided by a licensed professional who knows your health history.

Quick scoop, in plain language

  • Treating the flu: usually twice a day for 5 days.
  • Preventing the flu after exposure: usually once a day for at least 10 days ; sometimes longer in outbreaks.
  • Children and people with kidney disease get different schedules , so they cannot copy an adult’s dosing.

Information gathered from public forums or data available on the internet and portrayed here.