Tamiflu (oseltamivir phosphate) prescription available online

Tamiflu (Oseltamivir Phosphate) prescription treats flu (influenza) symptoms. Get flu relief with a new prescription or refill of Tamiflu today from a board-certified doctor online.*

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Reduces flu symptoms duration

Available as liquid or capsule

FDA-approved for Prophylaxis and Influenza

*Prescriptions are provided at the doctor’s discretion. Learn more about our controlled substances policy and how you can save up to 80% with our prescription discount card.

About Tamiflu (oseltamivir phosphate)

Tamiflu (oseltamivir phosphate) is an antiviral drug that kills the viruses that cause influenza virus and flu symptoms. The drug also effectively reduces the rate at which these viruses multiply and grow. Like any antiviral drug, this medication can only be used for viral infections caused by the flu (influenza) A or B strains. It is ineffective against bacterial infections because it will not stop bacteria from growing or kill the bacteria that cause these infectious diseases.

Some conditions that Tamiflu (oseltamivir phosphate) is known to treat include the flu virus infection caused by specific strains, including influenza viruses A and B. Tamiflu is available only by prescription. It is available in a generic formulation and under brand names, including oseltamivir phosphate. 

Tamiflu may be prescribed as a liquid or capsule to treat influenza. The capsules come in various sizes that correlate to their strength. The healthcare provider will prescribe a dose ideal for the severity of symptoms the patient experiences. The liquid form may be a more appropriate option for younger kids who develop signs of flu. It’s always important to follow the specific instructions on your prescription, as they can vary based on the formulation and dosage you are prescribed. 

If you are prescribed Tamiflu, be sure to complete the entire course of the antiviral drug unless your doctor specifically tells you to stop. This can also help to reduce the risk of circulating influenza viruses after you use the drug.

If you complete your prescription, the antiviral drug may only fully treat the flu virus. This could mean you will still develop a complete set of flu virus symptoms and may experience the condition over time.

Tamiflu (oseltamivir phosphate) prescription uses

There are 2 FDA-approved uses for Tamiflu, but it may also be used off-label to treat other conditions. Your online medical professional may prescribe it for the following reasons. It’s also possible that your healthcare provider may prescribe it for different reasons not listed here. Ask your online doctor or pharmacist if you have questions about why a medication is prescribed.

  • Influenza

    Influenza is a term that refers to flu that is caused by the influenza virus. This is a type of viral infection that generally affects the respiratory system. The virus can affect the nose, lungs, and throat. It is important to note that the influenza virus is not the same as the common flu. Tamiflu has been shown to relieve common symptoms associated with influenza viral infections adequately. The patient may experience a reduced duration of their symptoms when used to treat influenza. The drug also kills the specific bacteria that cause these symptoms to develop. 

    Based on clinical trials, the FDA recognizes Tamiflu's efficacy in treating flu symptoms. Several clinical trials have shown that it effectively reduces flu symptoms when used to treat influenza.

  • Prophylaxis

    While not a condition, Tamiflu is also FDA-approved as prophylaxis as an antiviral medication. In this case, the drug is provided to patients to reduce their risk of developing the influenza virus. Prophylaxis is an effective way to prevent the occurrence of influenza viral infection in cases where the patient may have been exposed to the virus. While effective, using Tamiflu as prophylaxis does not serve as a replacement for the flu vaccine.

    As a precaution, the FDA approves operating Tamiflu on patients 1 year of age and older to help reduce the risk of flu symptoms. Taken early, Tamiflu can ensure the flu virus does not cause viral infections in these patients. The Tamiflu dosage, in this case, may be lower. If you recently had a flu vaccination, you will not be given this medication as prophylaxis.

Tamiflu side effects

  • The side effects associated with taking Tamiflu are typically mild. Most Tamiflu side effects are associated with the respiratory and gastrointestinal tract. Tamiflu has some common side effects. They may include:


    When Tamiflu is used to prevent the development of flu, some patients may also experience pain throughout their bodies. 

    Other side effects, which are less common but might be more severe, could include:

    • Allergic reaction: It is pretty rare, but there are reports of people experiencing a severe allergic reaction to the chemicals used in Tamiflu. Patients who do experience an allergic reaction should promptly call the emergency department for treatment. Signs of an allergic reaction to Tamiflu may include itchiness and swelling in the face, throat, and tongue. A rash that develops on the skin is also another potential sign. Some people may experience severe breathing difficulties and dizziness if they have an allergic reaction to the Tamiflu medication. Severe allergic reactions can be life-threatening. Call the emergency services upon symptom onset to avoid severe illness and complications.


    You should call your doctor if you notice any of these side effects or develop other new or concerning symptoms while taking Tamiflu capsules.

How to take Tamiflu (oseltamivir phosphate)

Your pharmacist will provide you with instructions on how to take your Tamiflu prescription.

Be sure to read your prescription label and follow the instructions. Call your doctor or pharmacy if you have any questions.

Tamiflu can come in different forms and doses, so follow the specific instructions on your prescription. It is typically prescribed twice per day. Some particular instructions may include when you should be taking Tamiflu capsules for your flu symptoms. The doctor may also advise how long you should take the antiviral drugs to treat these flu symptoms that the influenza virus causes.

What to avoid while taking Tamiflu (oseltamivir phosphate)

Tamiflu has 8 known drug interactions. Don’t change what you take without checking with your doctor or pharmacist. That includes other medications or supplements, as well as over-the-counter drugs. 

Some of the drugs that Tamiflu is known to interact with potentially include:

  • Entecavir

  • Methotrexate

  • Probenecid

  • Warfarin

  • Pemetrexed

  • Tafamidis


It is important to tell your doctor if you had an influenza vaccination when taking Tamiflu. This antiviral drug is known to interact with the influenza h1n1 and live trivalent vaccines. With this in mind, note that Tamiflu capsules do not replace the influenza vaccination. It would be best if you still got an influenza vaccine. The influenza vaccine provides longer-term protection against the influenza virus.

It is also important to note that Tamiflu may not be suited to treat flu symptoms in individuals with existing health conditions. It has been found that Tamiflu may cause adverse interactions in patients with renal or hepatic impairment. You must speak with your healthcare provider if you have been diagnosed with these two conditions. They may suggest an alternative route to assist in the treatment of your flu or to implement a preventative strategy. 

Clinical trials have found that the active chemicals in these antiviral drugs can pass into breast milk. Thus, mothers should be careful when they use Influenza to treat influenza. Even though considered harmless for the breastfeeding baby according to these clinical trials, it is wise to consult your healthcare provider if you are currently breastfeeding and view an influenza Tamiflu treatment option.

Ask your doctor or pharmacist if it is acceptable to consume alcohol while taking Tamiflu to treat influenza.

Some research shows that regular alcohol consumption may adversely affect the immune system. This could affect the immune system's ability to ward off influenza viruses. Alcohol may also reduce the medication’s ability to do its job, making it harder to effectively kill off the viruses that cause influenza viral infection.

If you have experienced allergies to other medications, tell your doctor, even if you have not used Tamiflu or experienced allergic reactions to antiviral medicines. This can help to ensure the doctor monitors your progress more closely while you take the drug. It also ensures the doctor can provide adequate information about what to do in the case of allergic reactions.

Medication alternatives to Tamiflu (oseltamivir phosphate)

If your healthcare provider prefers to put you on another treatment, they may suggest another antiviral drug. Here are some common doctor-recommended alternatives based on your health issue:

  • Flu in adults

    In cases where an adult has the flu, there are more potent medications that may work more effectively and faster than Tamiflu:

    Xofluza (baloxavir marboxil)

  • Flu with renal conditions

    Due to the effects that Tamiflu may have on the renal system, particularly in cases where the patient has renal impairment, alternative drugs may be recommended in these cases:

    Relenza (zanamivir)

  • More severe flu symptoms

    If the patient has symptoms that require a more direct approach, intravenous administration of an antiviral drug may be considered. In this case, the healthcare provider may suggest the administration of Rapivab (peramivir) to provide fast and effective relief of symptoms. 

Tamiflu prescription FAQs

  • How much does Tamiflu cost?

    Tamiflu is available in different strength options. Multiple forms are also available, including capsules and a liquid opportunity that comes as an oral suspension. The pricing for these medications differs. Additionally, whether you prefer the brand name or the generic (oseltamivir) will significantly impact your price for the antiviral drug. You also need to consider the number of capsules you are prescribed. Other than these, consider the location and the pharmacy you use to refill your prescriptions. 

  • How can I refill my Tamiflu prescription?

    In most cases, you will not require a refill for Tamiflu. This is not a drug that is used as a long-term treatment solution. Instead, a healthcare provider will provide a prescription for a specific period. This usually includes taking two doses of the drug daily for around five days. When you are done with the medication but do not feel better, you should talk with your doctor before you opt for a prescription refill. You might need to change the type of drug you use to treat influenza. 

  • Is there any downside to taking Tamiflu?

    In some cases, people complain about side effects while using Tamiflu. These side effects are often mild and may include nausea and headaches. Gastrointestinal distress is experienced by individuals taking Tamiflu, but it is pretty rare. With this said, there are downsides to taking Tamiflu if you currently have impartments with your renal system. In this situation, speaking with your doctor about alternative ways to treat the flu symptoms you developed is better. 

  • What happens if I take Tamiflu but don’t have the flu?

    Sometimes, a healthcare provider may provide a patient with a Tamiflu prescription even if they do not currently present flu symptoms. This is called prophylaxis and focuses on preventing the onset of flu symptoms. It is essential only to take Tamiflu as prevention if your doctor recommends it. You should not experience any significant adverse events. However, some mild side effects develop when taking Tamiflu if they do not have flu. 

  • How long after taking Tamiflu should I feel better?

    Tamiflu starts to act quickly against the virus that causes the influenza viral infection. With this said, there is no specific time it will take to make you feel better if you have the flu. Instead, Tamiflu aims to reduce the days you will feel sick. In most cases, people experience flu symptoms for three to seven days. Taking Tamiflu early during the symptom onset may reduce the duration by one to two days. Thus, try to reach a healthcare professional when you first develop flu symptoms.

  • How long must you be on Tamiflu before you are not contagious?

    It depends on the severity of the flu and when you start to take Tamiflu. In most cases, Tamiflu can help to shorten the time it takes to recover from flu by up to two days. People are most contagious with flu during the first three to four days. With this in mind, Tamiflu may not significantly impact your contagious time. 

  • Who should not take Tamiflu?

    Due to the potential interactions with certain diseases, Tamiflu is not appropriate for everyone. People with severe renal impairment should avoid the use of Tamiflu. People with end-stage renal disease should especially not use Tamiflu as a treatment for influenza. It is also essential to avoid using this drug if you have experienced allergic reactions to similar medications. You should also avoid this medication if you recently had an influenza vaccine. The drug is also not for severely immunocompromised patients with a weakened immune system. Do not take medicine if you recently received your yearly flu vaccine. Your healthcare provider may suggest an alternative if you have chronic lung disease.

  • What happens if I miss a dose of Tamiflu?

    If you miss a dose of Tamiflu, try to avoid taking a double dose on the next serving time. If it is too close to the next dose, you should not take an extra capsule to compensate for the missed dose. Take the missed dose as soon as you remember to if there is still adequate time toward the next dose that you should take. 

  • What happens if I take too much Tamiflu?

    If you take too much of this drug, you may experience certain adverse reactions. It is important to notify your healthcare provider as soon as possible. If you have trouble breathing, call the local emergency department promptly. 

3 simple steps to request your Tamiflu prescription today 

Step 1

Book a Tamiflu prescription request appointment.

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Step 2

Talk to your medical provider regarding your Tamiflu prescription. 

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Step 3

Pick up your Tamiflu prescription. 

We can send prescriptions to any local pharmacy.

Tamiflu prescription pricing details

How pricing works

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Paying without insurance

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30 days of free membership

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  • Unlimited messages with your Care Team

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  • Exclusive discounts on lab tests

  • Free memberships for your family

  • Cancel anytime

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