Dosing & Uses
Dosage Forms & Strengths
capsule
- 30mg
- 45mg
- 75mg
powder for oral suspension
- 6mg/mL
Influenza A and B Prophylaxis
75 mg PO qDay for at least 10 days
Dosing considerations
- Initiate within 48 hours of exposure
- For community outbreak, may administer for up to 6 weeks
Influenza A and B Treatment
75 mg PO q12hr for 5 days
Dosing considerations
- Initiate within 48 hours of influenza symptom onset
H1N1 Influenza A (Swine Flu) Prophylaxis (Off-label)
75 mg PO qDay
Dosing considerations
- Postexposure prophylaxis: Initiate within 7 days of exposure and continue for at least 10 days
- Preexposure prophylaxis (community outbreak): Initiate during potential exposure period and continue for 10 days after last known exposure
- Consider longer duration (>5 days) in severely ill patients who remain severely ill after 5 days of therapy
H1N1 Influenza A (Swine Flu) Treatment (Off-label)
75 mg PO q12hr for 5 days
Dosing considerations
- Initiate within 48 hours of influenza symptom onset
Dosage Modifications
Renal impairment
Treatment
- CrCl >60 to 90 mL/min: No dosage adjustment necessary
- CrCl >30 to 60 mL/min: 30 mg PO BID
- CrCl >10 to 30 mL/min: 30 mg PO qDay
- End-stage renal disease (ESRD), not undergoing dialysis: Not recommended (not studied)
- ESRD CrCl ≤10 mL/min; on hemodialysis: 30 mg PO immediately and then 30 mg after every hemodialysis cycle; treatment duration not to exceed 5 days
- ESRD CrCl ≤10 mL/min; on CAPD: Single dose of 30 mg administered immediately
Prophylaxis
- CrCl >60 mL/min: No dose adjustment necessary
- CrCl >30 to 60 mL/min: 30 mg PO qDay
- CrCl >10 to 30 mL/min: 30 mg PO every other day
- End-stage renal disease (ESRD), not undergoing dialysis: Not recommended (not studied)
- ESRD CrCl ≤10 mL/min; on hemodialysis: 30 mg PO immediately and then 30 mg after alternate hemodialysis cycle
- ESRD CrCl ≤10 mL/min; on CAPD: 30 mg immediately and then 30 mg once weekly
Hepatic impairment
- Mild-to-moderate: No doage adjustment necessary
- Severe: Not studied
Dosage Forms & Strengths
capsule
- 30mg
- 45mg
- 75mg
powder for oral suspension
- 6mg/mL
Influenza A and B Prophylaxis
<1 year
- Safety and efficacy not established for prophylaxis
1-12 years
- <15 kg: 30 mg PO qDay x10 days
- 15-23 kg: 45 mg PO qDay x10 days
- 23-40 kg: 60 mg PO qDay x10 days
- >40 kg: 75 mg PO qDay x10 days
≥13 years
- 75 mg PO qDay for at least 10 days
Dosing considerations
- Initiate within 48 hours of exposure
- For community outbreak, may administer for up to 6 weeks
Influenza A and B Treatment
<2 weeks
- Safety and efficacy not established for treatment
2 weeks to <1 year
- 3 mg/kg PO q12hr for 5 days
1-12 years
- <15 kg: 30 mg PO q12hr for 5 days
- 15-23 kg: 45 mg PO q12hr for 5 days
- 23-40 kg: 60 mg PO q12hr for 5 days
- >40 kg: 75 mg PO q12hr for 5 days
≥13 years
- 75 mg PO q12hr for 5 days
Dosing considerations
- Start within 24-48 hours of symptom onset
H1N1 Influenza A (Swine Flu) Prophylaxis (Off-label)
<1 year
- <3 months: Data limited; not recommended unless situation judged critical
- 3-5 months: 20 mg PO qDay x10 days
- 6-11 months: 25 mg PO qDay x10 days
≥1 year
- <15 kg: 30 mg PO qDay x10 days
- 15-23 kg: 45 mg PO qDay x10 days
- 23-40 kg: 60 mg PO qDay x10 days
- >40 kg: Administer as in adults
H1N1 Influenza A (Swine Flu) Treatment (Off-label)
Acute illness and age <1 year
- <3 months: 12 mg PO q12hr x5 days
- 3-5 months: 20 mg PO q12hr x5 days
- 6-11 months: 25 mg PO q12hr x5 days
Acute illness and age ≥1 year
- <15 kg: 30 mg PO q12hr x5 days
- 15-23 kg: 45 mg PO q12hr x5 days
- 23-40 kg: 60 mg PO q12hr x5 days
- >40 kg: Administer as in adults
Interactions
Interaction Checker
No Results

Contraindicated
Serious - Use Alternative
Significant - Monitor Closely
Minor

Contraindicated (0)
Serious - Use Alternative (0)
Monitor Closely (12)
- clopidogrel
clopidogrel decreases levels of oseltamivir by Other (see comment). Use Caution/Monitor. Comment: Clopidogrel may decrease serum concentrations of active metabolite(s) of oseltamivir. .
- influenza virus vaccine quadrivalent
oseltamivir decreases effects of influenza virus vaccine quadrivalent by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- influenza virus vaccine quadrivalent, adjuvanted
oseltamivir decreases effects of influenza virus vaccine quadrivalent, adjuvanted by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- influenza virus vaccine quadrivalent, cell-cultured
oseltamivir decreases effects of influenza virus vaccine quadrivalent, cell-cultured by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- influenza virus vaccine quadrivalent, intranasal
oseltamivir decreases effects of influenza virus vaccine quadrivalent, intranasal by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- influenza virus vaccine quadrivalent, recombinant
oseltamivir decreases effects of influenza virus vaccine quadrivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- influenza virus vaccine trivalent
oseltamivir decreases effects of influenza virus vaccine trivalent by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- influenza virus vaccine trivalent, adjuvanted
oseltamivir decreases effects of influenza virus vaccine trivalent, adjuvanted by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- influenza virus vaccine trivalent, recombinant
oseltamivir decreases effects of influenza virus vaccine trivalent, recombinant by pharmacodynamic antagonism. Use Caution/Monitor. Avoid administration of live attenuated influenza vaccine intranasal within 2 weeks before or 48 hours after administration of oseltamivir, unless medically indicated.
- pretomanid
pretomanid will increase the level or effect of oseltamivir by Other (see comment). Modify Therapy/Monitor Closely. In vitro studies demonstrated that pretomanid significantly inhibits OAT3; monitor for increased adverse effects and consider dosage reduction for OAT3 substrates.
- probenecid
probenecid increases levels of oseltamivir by Other (see comment). Use Caution/Monitor. Comment: Coadministration of probenecid results in a 2-fold increase in exposure to oseltamivir carboxylate because of a decrease in active anionic tubular secretion in the kidney. No dosage adjustments are required with probenecid coadministration.
- ublituximab
ublituximab decreases effects of oseltamivir by immunosuppressive effects; risk of infection. Use Caution/Monitor.
Minor (0)
Adverse Effects
1-10%
Abdominal pain
Conjunctivitis
Ear disorder
Epistaxis
Insomnia
Nausea
Vomiting
Vertigo
<1%
Aggravation of diabetes
Anemia
Arrhythmia
Confusion
Delirium
Hemorrhagic colitis
Hepatitis
Humerus fracture
Peritonsillar abscess
Pneumonia
Pseudomembranous colitis
Pyrexia
Rash
Seizure
Transaminases increased
Toxic epidermal necrolysis
Unstable angina
Swelling of face or tongue
Postmarketing Reports
Hypothermia
Diaper rash (2 weeks to <1 year of age)
Dermatitis
Urticaria
Eczema
Stevens-Johnson Syndrome
Erythema multiforme
Gastrointestinal bleeding
Abnormal liver function tests
Warnings
Contraindications
Hypersensitivity
Cautions
Use caution in patients with chronic cardiac disease, severre hepatic impairment, renal imapairment, respiratory disease
Delirium and abnormal behavior leading to injury, and in some cases resulting in fatal outcomes, reported in patients with influenza who were receiving therapy; relationship to therapy not established
Most effective when used within 24-48 hr of onset of symptoms
Safety and efficacy for prophylaxis of influenza not established for <1year of age
Oral suspension should be mixed prior to dispensing
Safety and efficacy in immunocompromised patients not established
Therapy is not a substitute for influenza virus vaccine
Serious skin/hypersensitivity reactions such as Stevens-Johnson Syndrome, toxic epidermal necrolysis and erythema multiforme; discontinue therapy and initiate appropriate treatment if allergic-like reactions occur or are suspected
Prescribers should be alert to potential for secondary bacterial infections and treat them as appropriate
Neuropsychiatric events
- Delirium and abnormal behavior leading to injury, including fatalities, reported postmarketing in patients with influenza receiving oseltamivir
- Because these events were reported voluntarily during clinical practice, frequency cannot be estimated, but occurrence is uncommon
- Reported primarily among pediatric patients and often had an abrupt onset and rapid resolution
- Unable to establish causality between these events and oseltamivir
- These events may occur in the setting of encephalitis or encephalopathy, but can occur without obvious severe disease; closely monitor oseltamivir-treated patients with influenza for signs of abnormal behavior
Oral suspension and hereditary fructose intolerance
- Fructose can be harmful to patients with hereditary fructose intolerance
- One dose of 75 mg oral suspension delivers 2 g of sorbitol; this is above the daily maximum limit of sorbitol for patients with hereditary fructose intolerance, and may cause dyspepsia and diarrhea
Pregnancy & Lactation
Pregnancy
There are no adequate and well–controlled studies in pregnant women to inform a drug–associated risk of adverse developmental outcomes; available published epidemiological data suggest that the drug, taken in any trimester, is not associated with an increased risk of birth defects; however, these studies individually are limited by small sample sizes, use of different comparison groups, and some lacked information on dose, which preclude a definitive assessment of the risk
Pregnant women are at higher risk of severe complications from influenza, which may lead to adverse pregnancy and/or fetal outcomes including maternal death, still births, birth defects, preterm delivery, low birth weight and small for gestational age
Animal data
- In animal reproduction studies, no adverse developmental effects were observed at clinically relevant exposures
Lactation
Based on limited published data, have shown the drug to be present in human milk at low levels considered unlikely to lead to toxicity in the breastfed infant; postmarketing experience has not reported any information to suggest serious adverse effects to drug exposure via breast milk in infants; it is not known if drug affects human milk production; developmental and health benefits of breastfeeding should be considered along with mother’s clinical need for therapy and any potential adverse effects on breastfed child from drug or from underlying maternal condition
Pregnancy Categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk. C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done. D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk. X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist. NA: Information not available.Pharmacology
Mechanism of Action
Inhibits viral neuraminidases; stops release of virus from cells and prevents virus from crossing mucous lining of respiratory tract
Absorption
Bioavailability: 75%
Peak plasma time: 2.5-6 hr
Distribution
Protein bound: 3% (oseltamivir carboxylase); 42% (oseltamivir)
Vd: 23-26 L
Elimination
Half-life: 1-3hr (oseltamivir); 6-10 hr (oseltamivir carboxylate)
Excretion: Feces; urine (>90% as oseltamivir carboxylate)
Administration
Oral Administration
Tablets and oral suspension may be take with or without food
Tolerability may be enhanced if taken with food
Emergency Preparation of Oral Suspension from 75 mg Capsules
Extemporaneously prepared oral suspension from capsules may be needed if commercially available oral suspension unavailable
Instructions below are for 100 mL of 6 mg/mL suspension
1. Place 7 mL of distilled water into a polyethyleneterephthalate (PET) or glass bottle
2. Empty content of eight 75-mg capsules (ie, 600 mg) into bottle
3. Gently swirl the suspension to ensure adequate wetting of the powder for at least 2 minutes
4. Slowly add 91 mL of Ora-Sweet, cherry syrup, or simple syrup
5. Close bottle and shake well for about 30 minutesInstruct patient to shake well before use
Stable for 5 days at room temperature or 5 weeks refrigerated at 2-8°C (36-46°F)
Images
BRAND | FORM. | UNIT PRICE | PILL IMAGE |
---|---|---|---|
oseltamivir oral - | 30 mg capsule | ![]() | |
oseltamivir oral - | 45 mg capsule | ![]() | |
oseltamivir oral - | 30 mg capsule | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 45 mg capsule | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 30 mg capsule | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 30 mg capsule | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 45 mg capsule | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 45 mg capsule | ![]() | |
oseltamivir oral - | 30 mg capsule | ![]() | |
oseltamivir oral - | 6 mg/mL suspension | ![]() | |
oseltamivir oral - | 30 mg capsule | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 30 mg capsule | ![]() | |
oseltamivir oral - | 6 mg/mL suspension | ![]() | |
oseltamivir oral - | 6 mg/mL suspension | ![]() | |
oseltamivir oral - | 45 mg capsule | ![]() | |
oseltamivir oral - | 45 mg capsule | ![]() | |
oseltamivir oral - | 30 mg capsule | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 45 mg capsule | ![]() | |
oseltamivir oral - | 6 mg/mL suspension | ![]() | |
oseltamivir oral - | 6 mg/mL suspension | ![]() | |
oseltamivir oral - | 75 mg capsule | ![]() | |
oseltamivir oral - | 6 mg/mL suspension | ![]() | |
Tamiflu oral - | 75 mg capsule | ![]() | |
Tamiflu oral - | 30 mg capsule | ![]() | |
Tamiflu oral - | 45 mg capsule | ![]() | |
Tamiflu oral - | 6 mg/mL suspension | ![]() |
Copyright © 2010 First DataBank, Inc.
Patient Handout
oseltamivir oral
OSELTAMIVIR - ORAL
(oss-el-TAM-eh-veer)
COMMON BRAND NAME(S): Tamiflu
USES: Oseltamivir is used to treat symptoms caused by the flu virus (influenza). It helps make the symptoms (such as stuffy nose, cough, sore throat, fever/chills, aches, tiredness) less severe and shortens the recovery time by 1-2 days.This medication may also be used to prevent the flu if you have been exposed to someone who already has the flu (such as a sick household member) or if there is a flu outbreak in the community. Talk to your doctor for more details.This medication works by stopping the flu virus from growing. It is not a substitute for the flu vaccine. (See also Notes section.)
HOW TO USE: Read the Patient Information Leaflet if available from your pharmacist before you start taking this medicine. If you have any questions, consult your doctor or pharmacist.Take this medication by mouth with or without food. You may take it with food or milk to minimize stomach upset. Take this medication as soon as flu symptoms appear or as soon as possible after you have been exposed to the flu. Oseltamivir works best if you start taking it within 2 days of either of these events.If you have the flu, take oseltamivir as directed by your doctor, usually twice a day for 5 days.To prevent the flu, take oseltamivir as directed by your doctor, usually once a day for at least 10 days. Follow your doctor's instructions for how long to take this medicine.The dosage is based on your medical condition, kidney function, and response to treatment. In children the dosage is also based on weight.If you cannot swallow the capsules, ask your doctor or pharmacist about the liquid suspension form of oseltamivir. If the liquid is not available and if directed by your doctor or pharmacist, you may open up the capsule and mix the contents with a small amount of sweetened liquid (such as regular/sugar-free chocolate syrup, corn syrup, caramel topping, or light brown sugar dissolved in water). Stir the mixture and take the entire dose.This medication works best when the amount of medicine in your body is kept at a constant level. Take this drug at evenly spaced intervals at the same time(s) every day. Continue to take it for the full time prescribed. Stopping the medication too early may allow the virus to continue to grow, which may result in a relapse of the infection or failure to protect you from the flu.Tell your doctor if your condition lasts or gets worse or if new symptoms appear.
SIDE EFFECTS: Nausea and vomiting may occur. If either of these effects last or get worse, tell your doctor or pharmacist promptly.Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.The flu itself or oseltamivir may rarely cause serious mental/mood changes. This may be more likely in children. Tell your doctor right away of any signs of unusual behavior, including: confusion, agitation, self-injury.A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.In the US -Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.
PRECAUTIONS: Before taking oseltamivir, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.Before using this medication, tell your doctor or pharmacist your medical history, especially of: kidney disease (including dialysis treatment).Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.This medication passes into breast milk but is unlikely to harm a nursing infant. Consult your doctor before breast-feeding.
DRUG INTERACTIONS: Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.Tell your doctor if you have received flu vaccine in the nose within 2 weeks before treatment with this medication. This medication may lower your protection from flu vaccine given in the nose. Wait at least 2 days after ending treatment with this medication before receiving flu vaccine given in the nose.
OVERDOSE: If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center.
NOTES: Do not share this medication with others.This medication is not a substitute for the flu vaccine. Consult your doctor about the risks and important benefits of receiving a yearly flu shot to lower your chances of getting the flu.
MISSED DOSE: If you miss a dose, take it as soon as you remember. If it is within 2 hours of your next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.
STORAGE: Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.
Information last revised March 2023. Copyright(c) 2023 First Databank, Inc.
IMPORTANT: HOW TO USE THIS INFORMATION: This is a summary and does NOT have all possible information about this product. This information does not assure that this product is safe, effective, or appropriate for you. This information is not individual medical advice and does not substitute for the advice of your health care professional. Always ask your health care professional for complete information about this product and your specific health needs.
Formulary
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