How Long Does the Flu Last?

When symptoms like a sore throat and stuffy nose set in, you often wonder two things: What is this, and how long will it last? You could be dealing with allergies, a cold, or the flu, and each has a different timeline. How long the flu lasts depends on your general health but in general usually lasts about one to two weeks.

In this article, we break down the lifecycle of the flu, including how long you may experience symptoms, when you are contagious, and how long you should avoid interacting with others. We also advise when you should consider seeing a doctor. 

How Long the Flu Lasts

The influenza virus causes the flu, a contagious respiratory sickness that affects the throat, nose, and sometimes the lungs. For healthy individuals, the flu is typically a fairly short-term illness, lasting no longer than a week or two. Luckily, you won’t feel miserable the entire time. Below is a timeline of a bout of the flu.

Incubation period

The time from when you’re exposed to a virus until symptoms first begin is called the incubation period. For the flu, this takes one to four days, with an average of two days. This means you may be contagious a day or two before symptoms start and can unknowingly spread the virus during that time.

Symptoms appear

Symptoms like cough, sore throat, fever, and runny nose generally show up one to four days after being exposed to the influenza virus. Not everyone has the same symptoms, and certain symptoms, like vomiting and diarrhea, are more common in children or with certain strains of the flu. If your symptoms are severe or you are immunocompromised, consider seeking medical care at this time. 

Symptoms peak

Flu symptoms generally peak two to four days after they begin, then begin to gradually improve on their own. You are also most contagious three to four days after symptoms start. Symptoms may include:

• Fever or chills
• Cough
• Sore throat
• Runny or stuffy nose
• Body aches
• Headaches
• Fatigue

Symptoms taper off

For otherwise healthy individuals, flu symptoms typically begin tapering off five days after they start. However, coughing and a general “sick” feeling may last for more than two weeks, especially for the elderly and those with chronic lung disease. 

Recovery

With rest, over-the-counter (OTC) medications, and plenty of fluids, you’ll be on the road to recovery in no time. However, even as you begin to feel better, it’s important to stay away from others for a little while to ensure you don’t spread the flu. You are contagious from 5-7 days after symptoms emerge, so it’s best to stay home for a week after you first begin feeling sick. If fever is one of your symptoms, stay home for at least 24 hours after your fever is gone. 

How Long Are You Contagious?

The flu virus is thought to spread by tiny droplets released into the air when sick people cough, sneeze, or talk. These droplets land on surfaces others may touch or go directly into the other person’s eyes, nose, or mouth causing them to get sick. 

If you have the flu, you were contagious even before you had symptoms. Before people start feeling symptoms, they are contagious for one or two days. Once symptoms start, you are contagious for the first five to seven days after getting sick. People with weakened immune symptoms or children, may be contagious for even longer. 

How to Treat the Flu

Prompt treatment with antiviral drugs, within two days of getting symptoms, may lessen symptoms and shorten the duration of your sickness by one or two days. They may also prevent severe complications like pneumonia. Not everyone needs antiviral drugs but those with compromised immune systems or the elderly may benefit. 

If you have the flu, be sure to stay home and distance yourself from others. If you do need to go out for any reason, wear a mask, cover your coughs and sneezes with a tissue, and wash your hands frequently. Allow yourself plenty of time to rest and be sure to keep yourself hydrated. 

When to See a Doctor

With proper self-care, the flu typically goes away on its own, especially if you are otherwise healthy.

However, certain high-risk people should seek medical care when they come down with the flu to help watch for and prevent any serious complications such as pneumonia.

This includes: 

• Adults 65 and older
• Anyone with chronic illnesses (especially those that affect the lungs or immune system)
• Pregnant people
• Very young children with severe symptoms

Antiviral medications can help make flu symptoms go away about one day faster.

However, these need to be started within 72 hours of symptoms appearing, they can have bothersome side effects, and they do not prevent serious complications like hospitalization, pneumonia, or death.

Your healthcare provider can help you determine if these medications are right for you.

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