Then you just need to give it time, because flu can linger. But better than any remedy is taking steps to avoid the flu. It helps you stay well and helps everyone around you, too. Across the country, those sick days add up, costing billions of dollars in lost productivity each year. Although Tamiflu can reduce the flu by roughly 1 to 2 days, the flu vaccine is still the best option for fighting flu. A doctor answers your questions about Tamiflu.
Learn more about vaccine availability. Advertising Policy. You have successfully subscribed to our newsletter. Related Articles. Can the Flu Trigger a Heart Attack? Trending Topics. What Parents Need to Know. Amantadine and rimantadine are antiviral drugs in a class of medications known as adamantanes, which target the M2 ion channel protein of influenza A viruses.
Therefore, these medications are active against influenza A viruses, but not influenza B viruses. Therefore, amantadine and rimantadine are not recommended for antiviral treatment or chemoprophylaxis of currently circulating influenza A viruses. Antiviral resistance and reduced susceptibility to the neuraminidase inhibitors and to baloxavir among circulating influenza viruses is currently very low, but this can change. For weekly surveillance data on susceptibility of circulating influenza viruses to antivirals in the U.
Influenza Surveillance Report. Influenza viruses with reduced susceptibility or resistance to antivirals can occur sporadically or emerge during or after antiviral treatment in some patients e. Oseltamivir resistance in influenza A H3N2 and A H1N1 pdm09 viruses can develop during treatment, particularly in young children Roosenhoff, external icon ; Lina, external icon ; , and immunocompromised persons Memoli, external icon. Human-to-human transmission of influenza A H1N1 pdm09 viruses with an HY mutation in viral neuraminidase conferring resistance to oseltamivir has been reported among severely immunocompromised patients in hospital units, Gooskens, external icon ; Chen, external icon ; and in the community Hibino, external icon ; Le, ; external icon Hurt, external icon ; Hurt, external icon ; Takashita, external icon , but currently appears to be uncommon.
Limited human-to-human transmission of influenza A H3N2 virus with reduced susceptibility to baloxavir has been reported sporadically in Japanese children Takashita, external icon ; Takashita external icon ; Imai, external icon , but currently appears to be uncommon.
Clinical trials and observational data show that early antiviral treatment can shorten the duration of fever and illness symptoms, and may reduce the risk of some complications from influenza e. Early treatment of hospitalized adult influenza patients with oseltamivir has been reported to reduce death in some observational studies. In hospitalized children, early antiviral treatment with oseltamivir has been reported to shorten the duration of hospitalization in observational studies.
Clinical benefit is greatest when antiviral treatment is administered early, especially within 48 hours of influenza illness onset in clinical trials and observational studies.
Table 1. Post marketing reports of serious skin reactions and sporadic, transient neuropsychiatric events 2 Chemo- prophylaxis 5 yrs and older 3 people with underlying respiratory disease e. Summary of Influenza Antiviral Treatment Recommendations. Antiviral treatment also can be considered for any previously healthy, symptomatic outpatient not at high risk for influenza complications, who is diagnosed with confirmed or suspected influenza, on the basis of clinical judgment, if treatment can be initiated within 48 hours of illness onset.
Figure: Guide for considering influenza testing and treatment when influenza viruses are circulating in the community regardless of influenza vaccination history 1 Complete footnotes for this algorithm are available. When indicated, antiviral treatment should be started as soon as possible after illness onset, ideally within 48 hours of symptom onset. However, antiviral treatment might have some benefits in patients with severe, complicated or progressive illness, and in hospitalized patients when started after 48 hours of illness onset.
Observational studies in hospitalized patients with influenza have reported that clinical benefit is greatest when oseltamivir is started within 48 hours of illness onset Hsu, external icon ; Louie, external icon ; Muthuri, external icon ; Muthuri, external icon. However, some studies suggest that antiviral treatment might still be beneficial in hospitalized patients when started up to 4 or 5 days after illness onset Louie, external icon ; Yu, external icon.
Antiviral treatment of pregnant women of any trimester with influenza A H1N1 pdm09 virus infection has been shown to be most beneficial in preventing respiratory failure and death when started within less than 3 days of illness onset, but still provided benefit when started 3—4 days after onset compared to 5 or more days Siston, external icon.
One observational study reported that initiating neuraminidase inhibitor treatment within 6 hours after hospital admission was associated with shorter duration of hospitalization versus starting antiviral treatment later Katzen, external icon. Another observational study reported that neuraminidase inhibitor treatment initiated at the time of hospitalization was associated with a significant reduction in hospital length of stay in patients with clinically suspected or laboratory-confirmed influenza A H1N1 pdm09 virus infection compared with later initiation or no NAI treatment Venkatesan, external icon.
Decisions about starting antiviral treatment should not wait for laboratory confirmation of influenza see resources regarding Clinical Description and Lab Diagnosis of Influenza for more information on influenza diagnostic testing.
Clinical benefit is greatest when antiviral treatment is started as close to illness onset as possible. While influenza vaccination is the best way to prevent influenza illness, a history of influenza vaccination does not rule out the possibility of influenza virus infection in an ill patient with clinical signs and symptoms compatible with influenza. Antiviral treatment also can be considered for any previously healthy, symptomatic outpatient not at high risk with confirmed or suspected influenza on the basis of clinical judgment, if treatment can be initiated within 48 hours of illness onset.
Multiple randomized controlled clinical trials RCTs and meta-analyses of RCTs have demonstrated efficacy of early initiation of treatment started within 48 hours of illness onset with neuraminidase inhibitors in reducing duration of fever and illness symptoms compared with placebo in otherwise healthy children and adults with uncomplicated influenza Hayden, external icon ; Monto, external icon ; Monto, external icon ; Nicholson, external icon ; Hedrick, external icon ; Treanor, external icon ; Whitley, external icon ; Heinonen, external icon ; Fry, external icon ; Whitley, external icon ; Kohno, external icon ; Hsu, external icon ; Jefferson, external icon ; Whitley, external icon ;, Dobson, external icon ; Malosh, external icon.
One randomized clinical trial in children with uncomplicated influenza demonstrated a modest reduction in duration of symptoms and influenza virus shedding in patients initiating treatment after 48 hours; post hoc analysis suggested that oseltamivir treatment initiated 72 hours after illness onset reduced symptoms by one day compared with placebo Fry, external icon.
For outpatients with acute uncomplicated influenza, oral oseltamivir, inhaled zanamivir, intravenous peramivir, or oral baloxavir may be used for treatment. The recommended treatment course for uncomplicated influenza is two doses per day of oral oseltamivir or inhaled zanamivir for 5 days, or one dose of intravenous peramivir or oral baloxavir for 1 day.
Only one randomized clinical trial has compared baloxavir to oseltamivir for treatment of influenza B. This study found that baloxavir treatment was superior to oseltamivir among outpatients with influenza B virus infection Ison, external icon. CDC does not recommend use of baloxavir for treatment of influenza in pregnant women or breastfeeding mothers. There are no available efficacy or safety data for baloxavir in pregnant women, and there are no available data on the presence of baloxavir in human milk, the effects on the breastfed infant, or the effects on milk production.
CDC does not recommend use of baloxavir for monotherapy of influenza in severely immunosuppressed persons. There are no available efficacy, safety, or resistance data for baloxavir monotherapy of influenza in severely immunosuppressed patients and emergence of resistance during treatment is a concern because of prolonged influenza viral replication in these patients.
There are no available data on the use of baloxavir for treatment of influenza more than 2 days after illness onset. Oral oseltamivir is preferred for treatment of pregnant women Rasmussen external icon ,; external icon. Pregnant women are recommended to receive the same antiviral dosing as non-pregnant people. Multiple recent studies have reported safe use of neuraminidase inhibitors during pregnancy Dunstan, external icon ; Xie, external icon ; Saito, external icon ; Wollenhaupt, external icon ; Beau, external icon ; Svensson, external icon ; Greer, external icon ; Graner, external icon ; Ehrenstien, external icon ; Chambers, external icon ; Bennekom, external icon ; ACOG Committee, external icon.
Baloxavir is not recommended for the treatment of influenza in pregnant women, as there are no available efficacy or safety data for baloxavir in this population. For patients with severe or complicated illness with suspected or confirmed influenza e.
There are insufficient data for inhaled zanamivir and intravenous peramivir in patients with severe influenza disease. There are no available data from clinical trials on use of baloxavir treatment in patients with severe influenza disease. For hospitalized patients with suspected or confirmed influenza, initiation of antiviral treatment with oral or enterically-administered oseltamivir is recommended as soon as possible.
Antiviral treatment might be effective in reducing morbidity and mortality in hospitalized influenza patients, especially adults, even if treatment is started more than 48 hours after onset of illness.
Inhaled zanamivir and oral baloxavir are not recommended because of the lack of data in hospitalized influenza patients.
There are also insufficient data for treatment of hospitalized influenza patients with intravenous peramivir. A randomized clinical trial external icon of baloxavir treatment of influenza in hospitalized patients aged 12 years and older is in-progress. For patients with lower respiratory tract disease, lower respiratory tract specimens, such as bronchoalveolar lavage fluid or endotracheal aspirates, are preferred; an oropharyngeal throat swab may be collected if lower respiratory specimens are not available.
Testing of lower respiratory tract specimens may detect influenza viruses when testing of upper respiratory tract specimens is negative.
Multiple respiratory tract specimens collected on different days should be tested if influenza virus infection is suspected but a definitive diagnosis has not been made.
The optimal duration and dosing of antiviral treatment are uncertain for severe or complicated influenza. Treatment regimens might need to be altered to fit the clinical circumstances. For example, clinical judgment should be the guide regarding the need to extend daily treatment regimens longer than 5 days for patients whose illness is prolonged. Critically ill patients with respiratory failure can have prolonged influenza viral replication in the lower respiratory tract and might benefit from longer duration of treatment.
Clinical judgment and virologic testing of lower respiratory tract specimens by real-time reverse transcription-polymerase chain reaction RT-PCR should guide decisions to consider treatment regimens longer than 5 days for hospitalized influenza patients with severe and prolonged illness.
Longer treatment regimens might be necessary in immunosuppressed people who may have prolonged influenza viral replication. Such patients are at risk of emergence of influenza viruses with reduced susceptibility or antiviral resistance during or after antiviral treatment. A higher dose of oral or enterically-administered oseltamivir has been recommended by some experts e. However, oral or enterically administered oseltamivir has been reported to be adequately absorbed in critically ill adults, with standard doses producing therapeutic blood levels Ariano, external icon , and available data suggest that higher dosing may not provide additional clinical benefit Abdel-Ghafar, external icon ; Ariano, external icon ; Kumar, external icon ; Lee, external icon ; South East Asia Infectious Disease Clinical Research Network, external icon.
Studies indicate that the exposure to oseltamivir carboxylate the active metabolite of oseltamivir is similar between obese and non-obese subjects for both 75 mg and mg doses given twice daily Ariano, external icon ; Jittamala, external icon ; Pai, external icon ; Thorne-Humphrey, external icon. For patients who cannot tolerate or absorb oral or enterically-administered oseltamivir because of suspected or known gastric stasis, malabsorption, or gastrointestinal bleeding, the use of intravenous peramivir should be considered Lee, external icon ; deJong, external icon ; Ison, external icon ; Ison, external icon.
Resistance and reduced susceptibility of influenza viruses to antiviral drugs can also occur spontaneously, with no known exposure to antiviral medications Hurt, external icon ; Takashita, external icon ; Takashita, external icon.
This includes conservation of antiviral supplies and prioritizing use for those individuals at the highest risk for complications. Due to increased demands, however, the FDA also authorized the emergency use of peramivir, an investigational neuraminidase inhibitor that is administered intravenously.
Convenient care and office settings often use rapid influenza diagnostic tests RIDTs to identify the presence of influenza A and B viruses because these tests yield results in less than 15 minutes.
It is important to note that false-negative results are common, especially when influenza activity is high. Tests such as real-time polymerase chain reaction and viral culture have increased accuracy and sensitivity, but time and availability constraints limit the use of these methods. It is important that providers continue to exercise clinical judgment and not withhold antiviral treatment for patients with symptoms of influenza due to a negative test, particularly in highrisk populations.
In addition to not withholding treatment based solely on RIDT results, providers must also be mindful of clinical situations when antiviral treatment is not indicated. Antiviral treatment may be considered in these patients if they present within the first 48 hours of illness; those who present more than 48 hours after illness onset are unlikely to benefit from antivirals and should not be treated with them. There are currently 2 classes of antiviral medications available for the treatment and prevention of influenza: neuraminidase inhibitors oseltamivir, zanamivir and peramivir and adamantanes amantadine and rimantadine.
Oseltamivir Tamiflu , zanamivir Relenza , and peramivir Rapivab can be used to treat both A and B strains of the influenza virus, while amantadine and rimantadine are only effective against influenza A.
Due to the high rates of resistance among the influenza A viruses, only neuraminidase inhibitors are recommended for use in the influenza season.
Neuraminidase inhibitor antiviral therapy has the greatest benefit when given within the first 24 to 30 hours and in patients who present with fever, and can shorten the duration of influenza symptoms by approximately one-half day to 3 days. Some studies suggest that antiviral treatment might still be beneficial in hospitalized patients when started up to 4 or 5 days after illness onset.
Adequate hydration, ventilation, and prevention of secondary bacterial infection also prove to be critical for the care of severely ill patients with influenza. Concerns regarding trends of increased resistance in both antiviral medications should be considered when deciding which patients to treat.
Current data also show high rates of resistance among circulating influenza A strains to the adamantane class. Treatment of influenza with oseltamivir is recommended for 5 days with twice-daily dosing in people 2 weeks of age and older and should be considered first-line treatment during pregnancy. Treatment plans should be based on a total assessment of the patient to ensure that high-quality, evidence-based care is rendered. It is important to monitor weekly surveillance of local influenza activity and for circulating strains that may be resistant to current treatment recommendations.
Observational studies have found benefit in early initiation of antiviral treatment less than 48 hours from symptom onset , as well as when treatment is started up to 5 days after symptom onset, the greatest benefit being with earlier treatment.
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