Tamiflu vs. Xofluza: Differences, similarities, and which one is better for you

In this article:

• Main differences
• Conditions treated
• Efficacy
• Coverage and cost comparison
• Common side effects
• Interactions
• Warnings
• FAQs
• Bottom line

In this article

• Main differences
• Conditions treated
• Efficacy
• Coverage and cost comparison
• Common side effects
• Interactions
• Warnings
• FAQs
• Bottom line

When flu season hits, it can help to know you have potential treatment options. Along with the protection of the yearly flu shot, prescription medicines like Tamiflu and Xofluza can lessen symptoms and may shorten how long the illness lasts. Both antiviral medications are approved by the U.S. Food and Drug Administration (FDA), but they differ in how they work, how they’re taken, and how much they cost.

Let’s compare Tamiflu vs. Xofluza so you can make an informed choice if you come down with the flu.

Main differences between Tamiflu vs. Xofluza

	Tamiflu	Xofluza
Drug class	Antiviral Neuraminidase inhibitor	Antiviral Polymerase acidic (PA) endonuclease inhibitor
Brand/generic status	Generic version available	Generic version not currently available
What is the generic name?	Oseltamivir phosphate	Baloxavir marboxil
What form(s) does the drug come in?	Oral capsule Powder for oral suspension	Oral tablet Oral suspension bottle Packet for oral suspension
What is the standard dosage?	Treatment of influenza: 13 years or older: 75 mg twice daily for 5 days 1 to 12 years old: Dosage depends on weight, twice daily for 5 days 2 weeks to less than 1 year old: 3 mg/kg twice daily for 5 days Prevention of influenza: 13 years and older: 75 mg once daily for at least 10 days 1 to 12 years old: Dosage depends on weight, once daily for 10 days	Treatment or prevention of influenza: 5 years and older with a body weight of at least 80 kg (176 lbs or more): 80 mg taken as a single dose 5 years and older with a body weight of 20 to less than 80 kg (44 to 176 lbs): 40 mg taken as a single dose 5 years and older with a body weight of less than 20 kg (44 lbs): 2 mg/kg as a single dose (oral suspension only)
How long is the typical treatment?	Treatment of influenza: 5 days Prevention of influenza: 10 days *Preventive treatment during a community outbreak may last up to 6 weeks	Treatment or prevention of influenza: 1 day with a single dose
Who typically uses the medication?	Treatment of influenza: Adults, children, and infants 2 weeks of age and older Prevention of influenza: Adults and children 1 year of age and older	Treatment and prevention of influenza: Adults and children 5 years of age and older

What are the main differences between Tamiflu vs. Xofluza?

Tamiflu is the brand name for oseltamivir, first FDA-approved in 1999. It’s a neuraminidase inhibitor (NAI) that blocks the release of the influenza virus from infected cells, limiting its spread in the body. For treatment, it’s usually taken twice daily for five days, while for post-exposure prevention, it’s typically taken once daily for at least 10 days. Dosing is weight-based in children and often needs to be adjusted in people with kidney problems.

Xofluza is the brand name for baloxavir marboxil, which was approved in 2018. It works as a polymerase acidic (PA) endonuclease inhibitor that stops the flu virus from making copies of itself in a process known as viral replication. In this way, Xofluza works differently from other antiviral drugs like Tamiflu (oseltamivir) and Relenza (zanamivir). The drug only needs to be taken once as a single oral dose to treat or prevent the flu.

Conditions treated by Tamiflu and Xofluza

Both Tamiflu and Xofluza were developed as antiviral treatments for influenza. They are most effective when given at the first sign of symptoms and within 48 hours after symptoms appear. However, Tamiflu may also be recommended in certain hospitalized patients even after 48 hours. Xofluza isn’t currently recommended for severe cases during hospitalization.

Tamiflu and Xofluza can also be used to help prevent the flu (prophylaxis) in those in close contact with an infected individual. People with a higher risk of flu complications include those living in an area with a viral outbreak or those with a compromised immune system because of underlying medical conditions.

As antiviral treatments, Tamiflu and Xofluza are ineffective against fungal, parasitic, or bacterial infections. 

Is Tamiflu or Xofluza more effective?

Tamiflu and Xofluza help people recover from the flu faster than a placebo or no treatment. In clinical trials, Xofluza generally worked slightly quicker than Tamiflu.

• In one study (CAPSTONE-1), Xofluza shortened flu symptoms to around 54 hours, while Tamiflu worked in a similar timeframe. However, Xofluza reduced viral load (how much virus is in the body) more quickly than either placebo or Tamiflu.
• In another study with high-risk patients (CAPSTONE-2), Xofluza improved symptoms in about 73 hours versus 81 hours with Tamiflu. This difference was not statistically significant, and the study concluded that both drugs were similarly effective in shortening the time to improved symptoms.
• Other systematic reviews and meta-analyses suggest that Xofluza also caused fewer side effects and shortened flu symptoms more quickly than Tamiflu.

Tamiflu and Xofluza work about the same against the flu in real-world settings. The main differences are in how they’re taken and other factors like cost and availability.

Coverage and cost comparison of Tamiflu vs. Xofluza

Tamiflu is typically more affordable, especially in its generic form. Xofluza is only available as a brand-name drug, which may be more expensive.

Tamiflu vs. Xofluza cost

	Tamiflu	Xofluza
Typically covered by insurance?	Yes, depending on the plan	Yes, depending on the plan
Typically covered by Medicare?	Yes, depending on the plan	Yes, depending on the plan
Quantity	10, 75 mg capsules	1, 40 mg tablet
Typical Medicare copay	Varies	Varies
SingleCare cost	$18 at Kroger	$167 at Kroger

<small>Prescription drug prices often change. These are the most accurate medication prices at the time of publishing in ZIP code 23666 as of October 24, 2025. The listed SingleCare price references the price of generic drugs if available.</small>

Common side effects of Tamiflu vs. Xofluza

Tamiflu and Xofluza can cause many of the same possible side effects, such as nausea and headache. However, the likelihood of each side effect can vary between the two medications.

The most common side effects of Tamiflu include:

• Nausea
• Vomiting
• Headache
• Stomach pain (more often when used for prevention)

The most common side effects of Xofluza include:

• Diarrhea
• Sinusitis (inflammation of the sinuses)
• Bronchitis (inflammation of the lung airways)
• Headache
• Nausea

• Vomiting

Tamiflu is generally more likely than Xofluza to cause nausea and vomiting. Both drugs can also lead to more serious side effects in rare cases, including severe skin reactions and allergic reactions.

There have also been reports of psychiatric events such as delirium, hallucinations, and abnormal behavior in those taking Tamiflu. These psychiatric events have mostly been reported in children from Japan.

Drug interactions of Tamiflu and Xofluza

Tamiflu and Xofluza can interfere with the live attenuated flu vaccine (nasal spray). Therefore, it is recommended that you avoid live flu vaccines for at least two weeks before or two days after taking one of these antivirals.

Xofluza can interact with certain supplements and foods. Minerals like calcium, iron, magnesium, and zinc, as well as dairy products, can decrease the medicine’s effectiveness. Avoid taking Xofluza with medications that contain these minerals, including certain over-the-counter antacids and laxatives.

Warnings of Tamiflu and Xofluza

Tamiflu should be used with caution in people who have kidney problems since the drug can build up in the body, leading to an increased risk of side effects. Both Tamiflu and Xofluza can cause serious allergic reactions, including severe skin reactions. If a rash or other allergic symptoms appear, stop the medication and get medical help right away.

Tamiflu has also been linked to rare mental health side effects, such as confusion, hallucinations, or unusual behavior, mostly in children and adolescents. Xofluza isn’t recommended for children under 5 because resistance to the drug can develop more easily in this age group.

There is limited data on the use of Xofluza during pregnancy. Tamiflu is generally the preferred option in pregnant women. Consult a healthcare provider for treatment options while pregnant or breastfeeding. 

Frequently asked questions about Tamiflu vs Xofluza

Are Tamiflu and Xofluza the same?

Tamiflu and Xofluza are both antiviral medications. But they are not the same. Although they both improve flu symptoms, they work differently and may have different costs or side effects.

Is Tamiflu or Xofluza better? 

Tamiflu and Xofluza are both effective against the influenza virus. Xofluza is a newer drug that may help improve flu symptoms faster than Tamiflu, although studies show their overall effectiveness is similar. Xofluza only needs to be taken as a single dose, which some people may prefer. Consult healthcare provider for medical advice and more information on the best treatment.

Who can use Tamiflu and Xofluza?

Tamiflu and Xofluza treat uncomplicated influenza in adult and pediatric patients. Tamiflu is approved to treat the flu in adults and children aged 2 weeks and older and prevent the flu in adults and children 1 year and older. Xofluza is approved to treat or prevent the flu in adults and children 5 years and older. Both medications are generally safe in older adults 65 years and older. 

Can you take Xofluza with Tamiflu?

No. It is not recommended to take Xofluza and Tamiflu together. These drugs are prescribed as separate, individual options for the flu. One drug may be preferred depending on your medical history and overall condition.

Bottom line

Both Tamiflu and Xofluza are effective flu treatments. Xofluza may work faster and more conveniently, but it’s often more expensive than Tamiflu. Tamiflu is widely available in generic form and has a longer safety record.

Talk to your healthcare provider about which flu treatment is right for you. And don’t forget—you can save on both medications with the SingleCare prescription discount card.