What is Oseltamivir Phosphate: Uses, Warnings & Interactions

Updated Jan 13, 2021  •  Published Dec 30, 2020

Oseltamivir Phosphate overview

BRAND NAMES:

  • Tamiflu

Generic Names:

  • Oseltamivir Phosphate

Uses:

  • Treats and helps prevent influenza.

Therapeutic Classes:

  • Antiviral

Forms:

  • Capsule, Liquid

How it’s taken:

  • By mouth

What is Oseltamivir Phosphate used for?

Tamiflu is an antiviral medication that comes in capsule form. It is used to treat the influenza virus in people 2 weeks of age and older. It will not treat the common cold. You should not use this medication if you are allergic to oseltamivir. Common Tamiflu side effects may include nausea, vomiting, headache, and pain.

What form(s) does Oseltamivir Phosphate come in

  • Capsule

  • Liquid

What are common Oseltamivir Phosphate doses?

  • Capsule 30MG

  • Capsule 45MG

  • Capsule 75MG

  • Bottle 60ML of 6MG/ML

  • Box 10 Capsules

Common Oseltamivir Phosphate prescriptions

  • Oseltamivir Phosphate
    60ml of 6mg/ml bottle

  • Oseltamivir Phosphate
    10 capsules box

  • Oseltamivir Phosphate
    30mg capsule

  • Oseltamivir Phosphate
    45mg capsule

  • Oseltamivir Phosphate
    75mg capsule

  • Oseltamivir Phosphate
    10 capsules disp pack

How to take Oseltamivir Phosphate

  • Your doctor will tell you how much medicine to use. Do not use more than directed. Do not take this medicine for any illness other than the flu.

  • Start taking this medicine as soon as possible after flu symptoms begin or after you are exposed to the flu (within the first 2 days).

  • Shake the oral liquid before each use. Measure the liquid medicine with the oral dispenser that came with the medicine. Ask your pharmacist for an oral measuring spoon or syringe if you do not have one.

  • You may open the capsule and mix the contents with a sweet liquid (such as chocolate syrup, corn syrup, or sugar dissolved in water). Ask your doctor or pharmacist if you have any questions.

  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.

  • Missed dose: If you miss a dose and your next dose is due within 2 hours, skip the missed dose and take your medicine at the normal time. Do not use extra medicine to make up for a missed dose. If you miss a dose and your next dose is due in more than 2 hours, take the missed dose as soon as you can. Then take your next dose at the normal time, and go back to your regular schedule.

  • Capsules: Store at room temperature, away from heat, moisture, and direct light.

  • Oral liquid: Store in the refrigerator and use within 17 days. Do not freeze. You may also store the medicine at room temperature, but use it within 10 days. Throw away any medicine that has not been used within this time.

  • Capsules: Store at room temperature, away from heat, moisture, and direct light.

  • You may open the capsule and mix the contents with a sweet liquid (such as chocolate syrup, corn syrup, or sugar dissolved in water). Ask your doctor or pharmacist if you have any questions.

  • Shake the oral liquid before each use. Measure the liquid medicine with the oral dispenser that came with the medicine. Ask your pharmacist for an oral measuring spoon or syringe if you do not have one.

  • Missed dose: If you miss a dose and your next dose is due within 2 hours, skip the missed dose and take your medicine at the normal time. Do not use extra medicine to make up for a missed dose. If you miss a dose and your next dose is due in more than 2 hours, take the missed dose as soon as you can. Then take your next dose at the normal time, and go back to your regular schedule.

  • Start taking this medicine as soon as possible after flu symptoms begin or after you are exposed to the flu (within the first 2 days).

  • Read and follow the patient instructions that come with this medicine. Talk to your doctor or pharmacist if you have any questions.

  • Oral liquid: Store in the refrigerator and use within 17 days. Do not freeze. You may also store the medicine at room temperature, but use it within 10 days. Throw away any medicine that has not been used within this time.

  • Your doctor will tell you how much medicine to use. Do not use more than directed. Do not take this medicine for any illness other than the flu.

Oseltamivir Phosphate contraindications

  • This medicine is not right for everyone. Do not use it if you had an allergic reaction to oseltamivir.

Oseltamivir Phosphate warnings

  • This medicine is not a substitute for a yearly flu shot. It also will not prevent a bacterial infection.

  • Tell your doctor if you are pregnant or breastfeeding, or if you have kidney disease, liver disease, heart disease, lung disease, or a weakened immune system.

  • This medicine may cause the following problems: Serious skin reactionsUnusual thoughts or behaviors

  • Call your doctor if your symptoms do not improve or if they get worse.

  • The liquid form of this medicine contains sorbitol. Tell your doctor if you have hereditary fructose intolerance.

  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Oseltamivir Phosphate interactions

  • Do not use this medicine if you have received the live influenza vaccine (nasal mist) in the past 2 weeks or if you will receive the vaccine within 48 hours, unless your doctor says it is okay.

  • This medicine may cause the following problems: Serious skin reactionsUnusual thoughts or behaviors

  • Call your doctor if your symptoms do not improve or if they get worse.

  • The liquid form of this medicine contains sorbitol. Tell your doctor if you have hereditary fructose intolerance.

  • This medicine is not a substitute for a yearly flu shot. It also will not prevent a bacterial infection.

  • Keep all medicine out of the reach of children. Never share your medicine with anyone.

Oseltamivir Phosphate side effects

Serious Side Effects

  • Confusion, agitation, seeing or hearing things that are not there, change in mood or behavior, seizures

  • Blistering, peeling, red skin rash

  • Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing

  • Fever, chills, cough, sore throat, body aches

Less Serious Side Effects

  • Nausea, vomiting, diarrhea, stomach pain, or upset stomach