Facts About Flu Drugs

[Virtually Speaking]

Every year, millions of people in the United States get the flu. Influenza (flu) causes 36,000 deaths and 114,000 hospitalizations each year.

There are three types of flu viruses – type A, B, and C. Types A and B flu are responsible for the widespread outbreaks that occur almost every winter. Type C usually causes a mild respiratory illness (or may not produce symptoms at all) and does not cause flu epidemics.

Uncomplicated influenza gets better with or without treatment, but can cause considerable discomfort during the course of the illness. Many people use over-the-counter medications to ease flu symptoms. Because flu is a viral infection, it can be treated with an antiviral medication (if your doctor feels it's appropriate). Antibiotics are not an effective treatment for the flu. Antibiotics are medicines that kill bacteria and are not effective against viral infections.

There are four antiviral prescription drugs on the market that treat flu. These medications attack the virus that causes the flu, thus shortening the time it takes for symptoms to improve in uncomplicated cases of types A and B influenza.

“These drugs are not a cure for the flu,” says Thelma Hoehn, family nurse practitioner at GMH’s Neighbor Care Clinic in Valley View. “They don’t make people instantly better, but they may save flu sufferers a day or two of aching and sniffling.”

The U.S. Food and Drug Administration (FDA) approved Symmetrel (amantadine) in 1976. Taken orally in pill form, Symmetrel is approved to treat and prevent type A flu in adults and children 1 year old or older.

Flumadine (rimantadine), a derivative of amantadine, was approved in 1993. Also taken orally in pill form, Flumadine is approved for treating and preventing uncomplicated type A flu in adults and for preventing (but not treating) type A flu in children 1 year old or older.

“Symmetrel and Flumadine are used primarily in nursing homes to control outbreaks of flu,” explains Hoehn. “These drugs are not generally recommended for widespread use in healthy people.”

The newer antiviral drugs, Relenza (zanamivir) and Tamiflu (oseltamivir), became available in 1999. Both drugs can reduce the severity and shorten the duration of types A and B flu. Relenza is approved for treating uncomplicated flu in people 7 years of age and older. Tamiflu is approved for treating uncomplicated flu in people ages 1 year of age or older and is approved for preventing types A and B flu in people 13 years of age and older.

Relenza is orally inhaled as a dry powder using a device called a “Diskhaler.” Two inhalations are recommended twice a day, morning and night, for 5 days. Tamiflu is available in pill or liquid form and is taken twice daily for 5 days.

“Flu drugs are meant to be taken within the first two days of experiencing flu symptoms,” stresses Hoehn. “That means if you arrive at the doctor’s office after experiencing symptoms for three or more days, it is too late to receive a flu drug. There is no information about how effective these drugs are if treatment is started more than two days after flu symptoms start.”

All of these drugs have side effects. Side effects may include nausea; vomiting; diarrhea; bronchitis; stomach pain; dizziness; headache; nervousness; insomnia; fatigue; cough; sinus inflammation; ear, nose and throat infections; irritability; drowsiness; and constipation.

"People should become familiar with the complete prescribing information when considering flu drugs," says Hoehn. "All four drugs have package inserts that provide information on possible adverse reactions. A doctor should be informed of any side effect that seems unusual or that is especially bothersome."

Anyone who is pregnant, nursing, or allergic to their ingredients, should not take flu drugs. Relenza is not recommended for people with chronic respiratory diseases such as asthma or COPD.

“Antiviral drugs are NOT meant to take the place of a flu shot,” says Hoehn. “A flu shot is the best way to prevent and control the flu.”

“Flu drugs do not eliminate the risk of flu complications, such as bacterial infections, viral pneumonia, and heart or other organ system problems,” Hoehn stresses. "Anyone taking a flu drug that does not get better, or experiences new symptoms, should talk with their doctor. A bacterial infection or other illness that may look like the flu may be present."