Common Cold

Reviewed/Revised Apr 2024
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What is the common cold?

The common cold is a viral infection. It's one of the most common illnesses people get.

  • Colds spread easily from person to person, especially within the first 2 days of symptoms

  • Symptoms include stuffy or runny nose, sore throat, tiredness, and sometimes a mild fever and go away on their own within 4 to 10 days

  • Being cold or wet doesn’t cause colds or make you more likely to get sick

  • Having yellow or green-colored mucus is normal in the later stages of a cold—it doesn't mean you need antibiotics or have a more serious infection

  • Decongestants and antihistamines can help cold symptoms feel better, but don’t give these medicines to children under 4 years old

  • Because colds are caused by viruses, antibiotics won't cure a cold or make it go away faster

What causes a cold?

Colds are caused by many different viruses. A group of viruses called rhinoviruses are the most common cause. Rhinoviruses tend to cause colds in the spring and fall.

You can get a cold by:

  • Touching an infected person’s hand after they’ve wiped or blown their nose

  • Touching something that an infected person has just touched

  • Wiping an infected child's nose

  • Breathing in the virus after an infected person coughs or sneezes

What are the symptoms of a cold?

At first, you have:

  • A scratchy or sore throat

  • A runny nose with thin, clear discharge (fluid)

  • Sometimes, a mild fever

Later, you have:

  • A stuffy nose or a runny nose with thick yellow or green discharge

  • Feeling tired and sick

  • A cough, which may linger for up to 2 weeks

See a doctor right away if you have a high fever, a very bad headache, a rash, trouble breathing, or chest pain. You likely have an infection more serious than a cold.

Colds can cause asthma attacks in people with asthma. Colds can also lead to ear or sinus infections.

How can doctors tell if I have a cold?

Doctors can usually tell you have a cold based on your symptoms.

How are colds treated?

Doctors may tell you to:

  • Rest at home

  • Drink plenty of fluids

  • Use a humidifier or vaporizer at night to sleep more comfortably

Doctors may also suggest over-the-counter medicines to help you feel better while you wait for your cold to go away:

  • Decongestants can open up a stuffy nose

  • Antihistamines can dry up a runny nose and stop sneezing

  • Certain cough medicines can thin out mucus to make coughing easier or stop you from coughing

  • Gargling with salt water can help soothe a sore throat

You may find 2 or more of these medicines in one product, like a cough and cold medicine. Talk to your doctor or pharmacist if you have questions about cold medicines.

Decongestants and antihistamines can cause side effects in very young children. They should not be given to children younger than 4 years old. Salt water nose drops can be given to young children and can help open up a stuffy nose.

Antibiotics and existing antiviral medicines don't work against colds.

How can I prevent colds?

Washing your hands often with soap and water is the best way to keep from getting a cold.

If you have a cold, take steps to keep others from catching it:

  • Sneeze or cough into a tissue and put the used tissue in the trash

  • Wash your hands or use a hand sanitizer after touching used tissues, even your own

  • Clean household objects, such as toys and door handles, with a disinfectant (a liquid that kills germs)

  • Stay home from work or school until your symptoms start to go away—you may want to sleep in a different room from healthy family members

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