"The FDA has approved a new flu medication in the form of a singledose pill.  The medication called XOFLUZA was designed to make the flu shorter if taken within  hours of onset and can be prescribed to patients  and older once theyve been diagnosed with the illness according to the FDA.  The new medication is designed to significantly reduced the duration of flu symptoms by more than one day when compared to a placebo in clinical trials the FDA said. MORE Flu season is here What you need to know httpsabcnews.go.comHealthfluseasonfluvaccinestoryid Researchers believe the medication will prevent patients from spreading the flu which could help reign in contagion rates following the  flu season which saw  hospitalizations and  deaths  the deadliest season in four decades according to the FDA. The medication was approved under a priority review.  The medication is the first in a new class of antiviral medications that blocks an enzyme within the flu virus which stops viral replication early in the influenza cycle the FDA announced. XOFLUZA is similar to Oseltamivir also known under the brand name Tamiflu but decreases viral shedding faster and is associated with less side effects Dr. Todd Ellerin the infectious disease specialist at South Shore Hospital in Massachusetts told ABC News.  Like Tamiflu it seems to work better the quicker it gets into the patient Ellerin said. MORE The new flu vaccine recommendations as flu season approaches httpsabcnews.go.comHealthWellnessfluvaccinerecommendationsfluseasonapproachesstoryid In clinical trials XOFLUZA demonstrated efficacy against a wide range of influenza including Tamifluresistant strains and has also proved effective against some strains of Asian bird flu such as HN according to the FDA.  The medication is the first new flu medicine of its kind  with a novel proposed mechanism  in nearly  years said Dr. Sandra Horning chief medical officer and head of global product development at Genentech the company selling the pill in the U.S. in a statement to ABC News.  If patients see their doctors within  hours of symptom onset one dose of XOFLUZA can significantly reduce the duration of flu symptoms Horning said.  Since it was tested in healthy adult patients it is unclear how effective it will be in the most severe cases or for the most vulnerable patients Ellerin said. MORE Flu shot myths such as that you should wait for cold weather to get the vaccine httpsabcnews.go.comHealthflushotmythswaitcoldweathervaccinestoryid The pill will be available across the U.S. in the coming weeks according to the FDA."