It can be hard to tell the difference between the flu and the common cold, since the symptoms can be similar. But if you know the warning signs of flu, you can get treatment quickly and work on feeling better, sooner.
Unlike a cold, flu symptoms usually come on suddenly. Another key sign is a fever, which may not happen with a cold. You might also have:
Severe aches in your joints and muscles
Pain and tiredness around your eyes
Weakness or fatigue
Warm, flushed skin and red, watery eyes
Sore throat and runny nose
Adults with seasonal flu don’t usually vomit or have diarrhea, but children might. Some symptoms can mean your illness is severe. Get immediate medical help if you have any of the following:
Trouble breathing or shortness of breath
Pain or pressure in your chest or belly
Will My Symptoms Get Worse?
Most people recover in a few days to less than 2 weeks. But the flu can turn into more serious complications, like bacterial pneumonia, ear infections, sinus infections, meningitis, and dehydration. You’re at a higher risk for these problems if you’re 65 or older, or if you have certain medical conditions, like:
Heart problems, like congestive heart failure
Brain or nervous system conditions
Blood disorders, such as sickle cell disease
COPD, cystic fibrosis, and other lung diseases
A weak immune system because of a disease, like cancer or HIV/AIDS, or a medication
In most cases, the best way to treat the flu is to:
Rest at home.
Drink plenty of fluids.
Avoid contact with other people.
But people who are very sick or who have other medical conditions may need treatment with prescription medications, called antiviral drugs.
Antiviral drugs -- Relenza and Tamiflu -- are most effective when you take them within 48 hours after you start showing symptoms of flu. They can shorten the length of your illness by 1 day if you take them within this early window. They may also help even after the 2 days, especially in people who are very sick.
Your doctor may want you to take antiviral drugs if you have a high risk of complications from the flu.
When Is Flu Season?
Seasonal flu follows a fairly predictable pattern, starting in the fall and ending in the spring. A good sign that it’s started is the sudden rise in the number of school-aged children sick at home with flu-like illness. This first outbreak is soon followed by a flu uptick in other age groups, especially adults.
CDC: "Key facts about seasonal influenza (flu)," "Questions and Answers: Swine Flu and You," "Key Facts about Swine Influenza (Swine Flu)." “What You Should Know about Antiviral Drugs,” “The Flu: What To Do If You Get Sick.”
National Institute of Allergy and Infectious Diseases: "Flu (Influenza): Symptoms."
National Jewish Medical and Research Center: "Influenza and the Flu Vaccine."
Asthma and Allergy Foundation of America: "Flu (Influenza)."
American Lung Association: "Influenza Fact Sheet."
Amita Shroff, MD on September 11, 2013