How Safe Is Tamiflu in Children?

The facts and fallacies about the popular flu drug

Boy taking medicine
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Tamiflu (oseltamivir) is a popular, oral antiviral drug used to treat or prevent the flu (influenza). It has been approved by the U.S. Food and Drug Administration (FDA) to treat children two weeks of age or older and to prevent the flu in children three months or older.

Despite its popularity, the use of Tamiflu in children remains somewhat controversial. It is not uncommon to hear parents claim that it doesn't always work or to read reports suggesting that overuse can lead to the development of treatment-resistant influenza strains.

What does the research actually tell us?

Benefits of Taking Tamiflu

According to a report from the Centers for Disease Control and Prevention (CDC), the early use of antiviral drugs like Tamiflu can reduce the duration of flu symptoms, including fever, and may even lessen the risk of complications (including pneumonia, respiratory failure, and death).

Tamiflu is one of three antiviral drugs approved for this use, which also include the intravenous drug Rapivab (peramivir) and the inhaled drug Relenza (zanamivir). Unlike other antivirals used to treat the flu, these three drugs are effective in treating both influenza A and influenza B viruses.

Tamiflu is also important for children who cannot get a flu shot, such as those who have had a previous allergic reaction to a vaccine.

Downsides of Taking Tamiflu

Despite evidence supporting the use of Tamiflu in children, there are a number of barriers that have prevented parents from using it.

Price is chief among the concerns, with a five-day course of running as high as $100. While lower-costs generics are now available, the price is still significant.

More concerning yet is the belief that the drug doesn't actually work. In most cases, however, this is related to more to product misuse than to the drug itself.

Practically speaking, the effectiveness of Tamiflu can vary by when the treatment is started. To this end, most doctors recommend that the drug is taken within 24 hours of the first appearance of symptoms. The problem, of course, is that parents can sometimes miss minor symptoms like sniffles or a scratchy throat, particularly if the child seems otherwise well.

Moreover, the drug won't outright "kill" the virus once infection has taken place but rather shorten the duration and severity of symptoms.

On the other hand, Tamiflu can be extremely effective in a child hasn't yet been vaccinated and has been around other children with the flu. However, because the benefits are largely invisible, parents will often dismiss its use in flu prevention and only reach for it when symptoms appear.

Tamiflu Side Effects

Parent often associate price with potency and fear that a drug like Tamiflu may cause more symptoms than they relieve. For the most part, this is untrue.

According to the FDA, the two most common side effects are nausea and vomiting, which are usually not all that severe and occur within two days of starting treatment Taking Tamiflu with food can usually lessen the risk of these side effects.

Others may include mild stomach pain, nosebleeds, headache, and fatigue.

More serious side effects have been reported. One study in Japan had suggested that Tamiflu increased the risk of neuropsychiatric symptoms such as confusion and hallucinations and could lead to thoughts of self-harm or suicide in teens. This followed reports in 2005 that two teens had committed suicide shortly after using the drug.

To date, no similar events have been reported, and, from a global perspective, a post-market analysis did not find any increased risk of neuropsychiatric effects in users. With that being said, updated product labeling includes an advisement that hallucinations, self-injury, and abnormal behavior, while exceedingly rare, are possible.

Concerns About Resistance to Tamiflu

As with antibiotics used to treat bacterial infections, there have long been concerns that the widespread use of antiviral flu medications could lead to the development of a supervirus.

To date, we have not seen this. According to the CDC, resistance to Tamiflu was seen in one strain of the H1N1 virus in 2009 but in only one percent of samples. As such, the CDC currently considers the risk low but continues to monitor in case the incidence increases.

As of now, resistance to other strains of the influenza A or B virus has not been seen.

Sources:

Centers for Disease Control and Prevention. "Influenza Antiviral Medications: Summary for Clinicians." Atlanta, Georgia; updated October 26, 2017.

Fiore, A.; Fry, A.; Shay, D. et al. "Antiviral Agents for the Treatment and Chemoprophylaxis of Influenza: Recommendations of the Advisory Committee on Immunization Practices (ACIP)." MMWR. January 21, 2011; 60(RR01):1-24. PMID: 21248682.

U.S. Food and Drug Administration. "Tamiflu Pediatric Adverse Events: Questions and Answers." Silver Spring, Maryland; updated December 7, 2015.