Several antiviral drugs available for flu treatment

EDITOR’S NOTE: This is an article by local Centers for Disease Control Sentinel Physician Dr. Robert P. Blereau of Morgan City.
Several antiviral drugs are available by prescription for treatment and prevention of the flu.
These drugs are not a substitute for the flu shot.
Treatment with these drugs is best if started within 48 hours of flu symptom onset and may shorten the illness by about one day though later treatment may still be beneficial.
Treatment and prevention are indicated especially for those at high risk of complications from the flu including:
—Asthma.
—Neurologic and neurodevelopment conditions.
—Blood disorders (such as sickle cell disease).
—Chronic lung disease (such as chronic obstructive pulmonary disease and cystic fibrosis.
—Endocrine disorders (such as diabetes mellitus).
—Heart disease (such as congenital heart disease, congestive heart failure and coronary artery disease).
—Kidney disorders.
—Liver disorders.
—Metabolic disorders (such as inherited metabolic disorders and mitochondrial disorders).
—People who are obese with a body mass index of 40 or higher.
—People younger than 19 years of age on long-term aspirin- or salicylate-containing medications.
—People with weakened immune system due to disease (such as people with HIV or AIDS, or some cancers such as leukemia) or medications (such as those receiving chemotherapy or radiation treatment for cancer, or persons with chronic conditions requiring chronic corticosteroids or other drugs that suppress the immune system).
Other people at high risk from flu:
—Adults 65 years and older.
—Children younger than 2 years old (1).
—Pregnant women and women up to 2 weeks after the end of pregnancy.
—American Indians and Alaska Natives.
—People who live in nursing homes and other long-term care facilities.
(1) Although all children younger than 5 years old are considered at high risk for serious flu complications, the highest risk is for those younger than 2 years old, with the highest hospitalization and death rates among infants younger than 6 months old.
Treatment and prevention of the flu in children 5 years and older and young and middle-aged adults without comorbidities may not be warranted.
Four drugs are FDA approved for treatment and/or prevention of the flu at this time.
—Oseltamivir, generic for Tamiflu, is given twice a day for five days for treatment and once a day for 10 days for prevention.
It is the oldest and most commonly used drug and the only one available in generic.
It is available in liquid suspension and pill for all people beginning at 2 weeks of age.
Nausea and vomiting are its most common side effect and occurs very infrequently.
Oseltamivir dose may be decreased in those with severe kidney disease.
There are no known drug interactions.
In pregnancy, oseltamivir anti-flu oral treatment is recommended because it has the most studies regarding safety and efficacy.
—Zanamivir (Relenza) is a powder that is inhaled through a respiratory device making it cumbersome to use.
It can cause wheezing, its most common side effect, and is not recommended for those with respiratory problems such as asthma and COPD.
It can be used for treatment and prevention of the flu.
—Baloxavir (Xofluza) is a pill that is indicated as a single dose for early treatment but not for prevention of the flu in those 12 years and older.
It is not recommended for use in pregnancy, breast feeding, out patients with complicated or worsening illness, or hospitalized patients since no studies are available.
Its most common side effect is nausea in those 65 years and older.
Xofluza may interact with some medications including laxatives, antacids and supplements containing calcium, iron, magnesium, zinc or selenium.
The live flu vaccine should not be given within 14 days before or two days after Tamiflu or Xofluza administration.
—Peramivir (Rapivab) is given intravenously over 15 to 30 minutes as a single treatment dose for hospitalized seriously ill flu patients.
The dose may be repeated daily if deemed necessary.
Diarrhea is its most common side effect.
Amantadine and rimantadine, two of the first anti-flu drugs introduced decades ago, are no longer used because of development of high resistance of the flu virus to these drugs.