Diagnosis

Your health care provider may do a physical exam to look for symptoms of influenza, including H1N1 flu, often called swine flu. Or the provider may review your symptoms with you over the phone.

The provider may order a test that finds influenza viruses such as H1N1.

There are many tests used to diagnose influenza. But not everyone who has the flu needs to be tested. In most cases, knowing that someone has the flu doesn't change the treatment plan.

Care providers are more likely to use a test to diagnose flu if:

  • You're already in the hospital.
  • You're at high risk of complications from the flu.
  • You live with someone who is at greater risk of flu complications.

Your care provider may use a test to find out whether a flu virus is the cause of your symptoms. Or the tests may be used to get more information to see if another condition is causing your symptoms, such as:

  • Heart problems, such as heart failure or an infection of the heart muscle.
  • Lung and breathing problems, such as asthma or pneumonia.
  • Brain and nervous system problems, such as encephalopathy or encephalitis.
  • Septic shock or organ failure.

A test called polymerase chain reaction (PCR) may be used to see if you have the flu. It is more sensitive than other types of tests and may be able to find the flu strain.

It is possible to have both flu and another virus such as COVID-19 at the same time.

Treatment

Most people with flu, including H1N1 flu, need only symptom relief. Supportive care such as drinking liquids, taking pain relievers for fever and headache, and resting may be helpful.

If you have a chronic respiratory disease, your health care provider may prescribe medications to help relieve your symptoms.

Health care providers may prescribe antiviral drugs within the first day or two of symptoms. They can reduce the severity of symptoms and may lower the risk of complications.

The U.S. Food and Drug Administration has approved these four antiviral drugs to treat flu:

  • Oseltamivir (Tamiflu).
  • Zanamivir (Relenza).
  • Peramivir (Rapivab).
  • Baloxavir (Xofluza).

But flu viruses can develop resistance to these drugs. So health care providers reserve antivirals for certain groups. This includes people at high risk of complications and those who are in close contact with people who have a high risk of complications.

Using antivirals carefully makes development of resistance less likely and keeps supplies of these drugs for those who need them most.

Lifestyle and home remedies

If you develop any type of flu, stay home. Keep sick children home until the fever has been gone for 24 hours.

These measures may help ease your symptoms:

  • Drink plenty of liquids. Choose water, juice and warm soups to prevent dehydration.
  • Rest. Get more sleep to help your immune system fight infection.
  • Consider pain relievers. Use a nonprescription pain reliever, such as acetaminophen (Tylenol, others) or ibuprofen (Advil, Motrin IB, others). Use caution when giving aspirin to children or teenagers. Children and teenagers recovering from flu-like symptoms should never take aspirin. This is due to the risk of Reye syndrome, a rare but potentially life-threatening condition.

Avoid being around other people until you're feeling better, unless you're getting medical care. If you do need to leave your home and get medical care, wear a face mask. Wash your hands often.

March 23, 2023
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