by Terra Leon, PharmD Candidate 2019
Tamiflu (oseltamivir) is a prescription medication used in the treatment of influenza in patients 2 weeks and older. It can also be indicated as prophylaxis treatment from the flu and reduce the chances of getting the flu in patients 1 year and older1.
How does Tamiflu work?
Tamiflu (oseltamivir) is a prodrug, meaning that the drug is metabolized into the active drug after it is administered. Prodrugs are beneficial when the active drug itself has low availability in circulation and is not absorbed well in the stomach. Prodrugs are designed to not only increase the amount active drug in circulation, improve elimination but they also can reduce adverse effects or unintended side effects. Once Tamiflu is metabolized into the active drug, the active drug blocks replication of the virus in the body3. Tamiflu stops the replication process of the influenza virus in your body, it does not cure you of the flu rather it shortens the duration of flu like symptoms in the body by about 1-2 days.
Can everyone use Tamiflu?
Tamiflu (oseltamivir) is recommended in patients for treatment of influenza who are 2 weeks and older and is to be initiated within 48 hours of influenza symptom onset2. Tamiflu may also be prescribed for patients who were exposed to a confirmed flu diagnosis within 48 hours of close contact with the infected individual2. Patients who use Tamiflu >48 hours of symptom onset or exposure may still benefit from the medication, specifically children4. A study was done in children indicating that if Tamiflu was administered within 5 days of symptom onset that overall flu symptoms were reduced by 1 day when compared to placebo4.
Tamiflu side effects
The main side effects patients experience while using Tamiflu are headache, nausea and vomiting3. Please seek medical attention if you have any serious skin and hypersensitivity reaction.
Misconceptions about Tamiflu
Tamiflu will cure me of the flu
Most patients have the misconception that Tamiflu will cure them of the flu, when in reality the medication works by reducing the number of days with flu like symptoms. There is not direct cure for the flu since it is a viral entity, like the common cold. All we can do is treat our symptoms to ease the burden of the virus on the body. The most effective way to protect yourself from the flu is to receive your flu vaccination annually.
Tamiflu is a replacement for the flu shot
Tamiflu or any antiviral medication is not a replacement treatment for the flu vaccine itself. Receiving the flu vaccine is the primary defense to protect yourself from the flu. Antiviral medications are second line when the flu vaccine is not available or contraindicated for the individual4. Most insurance companies will cover the flu vaccine at little to no cost at all where Tamiflu (oseltamivir) can cost anywhere from $50-$135 depending on insurance and quantity needed5. That being said, receiving the flu vaccine protects you from the unwanted flu symptoms as well as the unwanted cost of medication, doctor office visits, and valuable time off work and school.
When I take Tamiflu I cannot get sick
There is no evidence that Tamiflu has any effect on any other illness in the body that does not contain influenza viruses, including bacterial infections. Some bacterial infections can initially present as influenza, it is important to be tested for influenza before starting Tamiflu as the sole treatment2. Always follow up with your doctor if you suspect a secondary bacterial infection in order to be treated appropriately.
- “Fever, aches, chills. Check your symptoms and learn more about a prescription flu treatment.” Tamiflu.havaswwsfdev.com. 2019. 15 Jan. 2019 <https://www.tamiflu.com/>.
- Tamiflu Prescribing Information. 2018. 15 Jan. 2019 <https://www.gene.com/download/pdf/tamiflu_prescribing.pdf>.
- “Tamiflu (oseltamivir).” Facts & Comparisons. 15 Jan. 2019 <https://fco.factsandcomparisons.com/lco/action/search?q=tamiflu&t=name&va=>.
- “Influenza (Flu).” Centers for Disease Control and Prevention. 22 Nov. 2013. Centers for Disease Control and Prevention. 15 Jan. 2019 <https://www.cdc.gov/flu/news/flu-antiviral-benefits.htm>.
- “Tamiflu (oseltamivir).” ScriptSave Wellrx. Feb 2019 https://www.wellrx.com/prescriptions/tamiflu/