How Long Does the Flu Last?

It’s flu season, and telltale symptoms lead to these obvious questions: “How long does the flu last?” and “How do I fight off the flu?

how long does the flu last

How long does the flu last? Too long, as any of us who have been leveled by a flu virus would attest. A number of strategies can help you fight off the flu—and, if you do get hit, to keep the duration as short as possible.

© Photographerlondon | Dreamstime

We all dread the day when we hear that the flu is going around—and then start to feel the first strains cropping up somewhere in our body. Every time you sneeze, cough, or feel a tingle in your throat, you wonder, “Is it my turn?” If and when you do come down with the flu, what can you expect? Just how long does the flu last, and how much will you suffer?

The short answer: A bout with the flu will typically run three to five days if you’re otherwise healthy and well—but, as we’ll discuss below, it can drag on longer for the elderly and the sick.

According to the Centers for Disease Control and Prevention (CDC), the flu is a “contagious respiratory illness caused by influenza viruses that infect the nose, throat, and lungs.” It can cause anything from a mild sniffle to a severe debilitating illness and even death. It’s hard to be certain how many people will get the flu in the U.S. every year—not all cases are confirmed and reported. But estimates tells us that between 5 and 20 percent of the population will catch it every year.

Between 1976 and 2006, flu-associated deaths have ranged from 3,000 to 49,000 each year. Those most severely effected, typically, are the elderly as well as people who have other chronic health problems. Annual healthcare costs associated with the influenza virus are well more than $10 billion in the U.S. alone.

Types of Flu Viruses

Two main types of flu virus affect humans: influenza A and influenza B. Most cases occur during a well-defined flu season every year, starting in early December and petering out in April, with a definite peak from mid-January through early February. If you’re ill during the mid-summer, it’s unlikely that you have the flu.

Many people who catch the flu will be unaware of how they got it and who may have infected them. The virus is spread by droplet infection, so may have been the man who sneezed next to you in the grocery store, or perhaps it was the kid with the cough who sat in front of you at the football game. Sometimes it sweeps through a school, workplace, or family, leaving in its wake a slew of sick people.

Do I Have the Flu? Common Symptoms of the Flu

If you have been exposed to a flu virus, it can take one to four days for symptoms to show themselves. You may start by feeling a little under the weather, or you may wake up one morning feeling like you’ve been hit by a truck.

Once you’ve contracted a flu virus, you may develop some of the following symptoms or—if you’re really unfortunate—all of them. Here are eight signs of the flu:

how long does the flu last

Flu symptoms commonly involve red and watery eyes and even photophobia—the condition where light hurts your eyes.

  1. High temperature, sweats, feeling feverish, or running hot one moment and then shaking with chills the next
  2. Runny or blocked nose, sore throat, and cough
  3. Racing heart
  4. Red and watery eyes, and sometimes photophobia (light hurts your eyes), burning sensation, or pain in the eyes
  5. Aches and pains
  6. Headaches in the forehead and around the eyes
  7. Severe tiredness/fatigue
  8. Stomach upset with vomiting and diarrhea (more common in children)

”How Long Does the Flu Last?” and Other Common Questions

Some strains of flu virus are more “virulent” than others; that is, they make people more unwell. Whether yours is a serious case or a mild flu, you’ll likely have these questions:

  • How long does the flu last? Flu symptoms usually persist for three to five days in people who are otherwise well. However, young children, pregnant women, the elderly, and people with chronic medical problems (like asthma, diabetes, cancer, HIV, and heart disease) may be knocked out for a longer period of time. They also may be more prone to complications and worsening of the underlying medical condition. The flu may leave even a healthy, young adult feeling weak and rundown for weeks.
  • How long is the flu contagious? You may be contagious for five to 10 days, so try and stay home if you think you have the flu. You may feel well enough to brave the outside world, but you don’t want to be responsible for passing it onto someone who is high risk and could get seriously ill. Good hand hygiene and covering your mouth and nose if you cough or sneeze may help curb the spread. (See also “How Long Does the Flu Last? Best Bets for Keeping It Short-Lived” section below.)
  • Can I protect myself against the flu? Many people opt to have a flu vaccine every year, as recommended by the CDC. The vaccine is not a guarantee, however, as the annual vaccine is created based on predictions of which strains will be around the following winter; sometimes these predictions are wrong. That said, people with chronic health problems or weak immune systems are more likely to get the flu, and many doctors strongly recommend they get vaccinated every autumn. As for healthy children and adults, the choice as to whether to have the flu vaccine is up to you: Discuss the pros and cons with your healthcare provider.

Complications of Influenza

Some people develop complications from the flu. When you have the flu, you’re more susceptible to secondary viruses and bacteria. Most commonly, they hit your nose, throat, sinuses, or lungs, causing pneumonia. Rarely, people go on to develop sepsis (blood infection) or inflammation of the heart, brain, or muscle.

If you have chronic medical problems, are pregnant, or are elderly, be very cautious with the flu. Don’t be a martyr; call your doctor for advice. If you’re a parent and your child is unwell with the flu, have him or her checked out.

how long does the flue last

Don’t underestimate the importance—and effectiveness—of washing your hands frequently to lessen your chances of contracting a flu virus.

Fighting the Flu: How to Overcome the Influenza Virus

The stronger your immune system, the less likely you are to catch and become ill with the flu. Take control of your health and boost your immune system by eating a well-balanced, healthy diet with lots of fruits and vegetables, and consider taking a vitamin D supplement.

Regular exercise also keeps your body, and particularly your lungs, healthy and reduces your risk of complications.

Hygiene is also important, especially during flu season. Wash your hands frequently, particularly when you get home from public places, and cover your mouth and nose if you hear someone sneeze in your vicinity.

How Long Does the Flu Last? Best Bets for Keeping It Short-Lived

As noted above, in most cases the flu lasts three to five days. While you’re in the throes of the virus, it’s important to listen to your body.

  • If you feel exhausted and weak, rest in bed and stay well hydrated.
  • Take over-the-counter medications such as cold-and-flu remedies or simple acetaminophen or ibuprofen. They may reduce fever, aches, and pains.
  • You may feel like treating yourself to a doughnut when you have the flu, but you’d be better off with a green salad, a bowl of blueberries, and hot water, honey, and lemon juice or apple cider vinegar. There is some research that an alkaline diet can help speed recovery from viruses.

See also our post “Best Flu Treatments: 7 Reliable Remedies for Relieving Flu Symptoms.”

Many people swear by natural remedies for the flu. As with most research on natural remedies, there is often no conclusive proof that they’re effective across the board, but they may work for you. There’s research, for example, that the following remedies may shorten the course of the flu: the Japanese herb maoto, licorice root, the Chinese herb Antiwei, North American ginseng, berries, Echinacea, plant-extracted carnosic acid, pomegranate, guava tea, and Bai Shao. Oral zinc, vitamin C, and probiotics can help, too. If you’re a tea drinker, you may like to try black (without milk), elderberry, green, echinacea, or licorice root teas.

(To learn more about natural remedies, click here. If you’re taking medications, always check that natural remedies do not interfere with them.)

Do I Need Antiviral Drugs to Treat My Flu?

Antiviral drugs can reduce flu symptoms, speeding recovery by one to two days, and may prevent serious complications. But they need to be given early in the infection and are usually prescribed for five days.


Not everyone with flu-like symptoms has the flu. Several other conditions mimic the flu, including other viruses like rhinovirus, respiratory syncytial virus (RSV), adenovirus and cytomegalovirus, and bacterial pneumonia.

If you have traveled abroad to tropical areas and are running a high fever, you may need to be screened for illnesses such as Dengue fever and malaria. Legionnaires’ disease is rare, but causes similar symptoms and affects people living in institutions or apartment blocks.

There are three drugs approved by the FDA for flu: oral oseltamivir (Tamiflu), oral zanamivir (Relenza), and intravenous peramivir (Rapivab) for people who are very sick. As with all medications, there may be side effects, among them nausea, vomiting, dizziness, runny or stuffy nose, cough, diarrhea, and headache.

Certain groups should be considered a priority for antiviral treatment: children under 5, people over 65, people with chronic medical conditions (especially asthma, diabetes, and HIV), pregnant women, people living in residential or nursing homes, people who are very overweight, and American Indians or Alaska Natives.

For most people, the flu is an unpleasant infection that lays them low for a few days. Bed rest, good hydration, and over-the-counter medications will suffice. For the high-risk minority, the influenza virus is much more serious; those who fall into this category need to be alert to worsening symptoms and quick to seek medical advice. Living a healthy lifestyle may decrease your odds of getting sick with the flu.

For more information on research-backed treatments for flu, check out our article Best Flu Treatments: 7 Reliable Remedies for Relieving Flu Symptoms.

Originally published in 2017, this post is regularly updated.

As a service to our readers, University Health News offers a vast archive of free digital content. Please note the date published or last update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.

Tags: , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Leonaura Rhodes, MD

Dr. Leonaura Rhodes is a physician turned author, coach, and freelance medical writer and editor. She has worked for Belvoir Media since 2017 and has authored hundreds of articles on … Read More

View all posts by Leonaura Rhodes, MD

Enter Your Login Credentials
This setting should only be used on your home or work computer.