In most cases, flu symptoms will subside after about four days. When the symptoms persist or worsen, it’s time to call the doctor. (For Spectrum Health Beat)

If you ever had the flu, you’ve likely asked yourself the dreaded question: Am I sick enough to merit a visit to the doctor, or will this crud just go away in time?

You might even be wondering if your condition is serious enough to warrant an emergency room visit.

To answer the latter: You should head to the emergency room if you’re having trouble breathing or you’re experiencing confusion, or if you have an extremely high fever or chest pain. The same applies if you’re coughing up blood or unable to take in fluids.

Hopefully, your condition will never reach that point.

As soon as you start to feel seriously ill you should schedule a visit with your primary care provider, call MedNow for a video visit with a provider, or head to an urgent care clinic.

The flu virus strikes tens of thousands of Americans every year.

Normal flu-like symptoms—cough, congestion and a sore throat—do not mean you need to go to the doctor right away. These types of symptoms should begin to subside within a few days.

You should call your doctor if the symptoms persist or worsen by Day 4.

And you should especially seek care if you are among the people more susceptible to complications, including the 65-and-older group, those with chronic illnesses and children age 5 and younger.

When conditions worsen beyond typical flu symptoms, it is important to seek medical attention.

Ignoring the problem can lead to secondary infections such as pneumonia or sepsis, a potentially life-threatening condition that occurs when the body’s immune system delivers an overwhelming response to an infection. Sepsis is most common and dangerous in older adults or those with weakened immune systems.

Dorine Berriel-Cass, manager for infection prevention with Spectrum Health, urges anyone who suspects they might have the flu to visit their primary care physician.

She also encourages people to get the flu vaccine if they haven’t already. It can lessen the severity of flu symptoms and reduce the odds of contracting the flu.

“Secondary infections are always a risk for those who are at high risk for the flu, including the very young, elderly and those with underlying medical conditions,” she said.

What should you do if you get the flu and your symptoms progress but you can’t get an immediate appointment with a primary care physician? Head to a nearby urgent care clinic or call MedNow.

And again, if you experience trouble breathing, confusion, extreme high fever or chest pain—or if you’re coughing up blood or you can’t take in fluids—you need to get to an emergency department.