The flu can make you feel miserable. But it's not usually serious. Most teens get better after resting at home for a couple of days. But a few people — especially those with other health problems — might get really sick.

So how do you know if you're sicker than you should be? Here are situations in which you need to get medical help.

Emergency Situations

Find someone to take you to the nearest emergency room (or, if you're alone, dial 911) if you have:

• Trouble breathing. Occasionally flu viruses cause chest infections like pneumonia. Because of these infections, some people will have difficulty breathing.
• Dehydration. Fever, vomiting, and diarrhea can cause people to lose more fluid than they take in. Occasionally this becomes serious and starts to affect how the body functions. Signs that someone may be dehydrated include feeling dizzy or lightheaded, dark-colored pee, or peeing a small amount and not very often.
• Feeling confused or "out of it." In very rare cases, the flu can lead to complications that may cause a person to feel spacy or out of it.

Are you babysitting or looking after a younger sibling who is sick? Get an adult's help immediately or call 911 if you notice a child has any of these problems:

• fast breathing or trouble breathing
• bluish skin color
• very sleepy or lethargic
• in babies, being so irritable they cannot be consoled
• fever with a rash

What if you're with someone older — like a friend or family member? If the person has trouble breathing or is not reacting normally to you, dial 911. But if someone is coughing a lot but breathing comfortably, or if the person is tired but able to talk and react, suggest he or she call a doctor.

Potentially Serious Situations

Some people need to pay extra attention when they get the flu. Call your doctor for advice if:

• You have another health condition. People who have other health problems (such as asthma or diabetes) are more at risk of complications from the flu.
• You are pregnant. Pregnancy can affect a woman's immune system, making her more vulnerable to flu and other viruses. Because of this, pregnant women are at higher risk of having complications from the flu — although most will recover without complications.
• Your flu symptoms get better but then come back. If your flu symptoms return with a fever and a worse cough, that can be a sign of another infection.
• Your flu symptoms are still getting worse after 5 days.

Most people who get the flu will get better on their own at home after a few days. But if you have other health conditions or start noticing any of the problems mentioned above, get medical help.

Reviewed by: Elana Pearl Ben-Joseph, MD
Date reviewed: October 2011