When to See a Doctor About Cold and Flu Symptoms

Signs and Symptoms That Require Immediate Medical Care

Most people don't go to the doctor when they have a cold or even the flu. In most cases, staying at home, resting, hydrating, and taking over-the-counter medications is all that's needed. But there are also times when certain symptoms warrant a visit to a doctor or even the emergency room. Knowing when to act can help you potentially avoid progression of your illness, as well as serious complications.

This is especially true for people in high-risk groups, such as young children, pregnant women, adults 65 and older, and people with certain health conditions, in whom complications are more likely.

Fever

Surprisingly, the decision as to when to see a doctor about a fever often has little to do with how high the fever is—at least in adults. According to the Centers for Disease Control and Prevention (CDC), a flu-related fever that improves but suddenly returns or worsens is the key warning sign that you should seek medical attention.

The issue is different in kids. Any child who experiences fever above 104 degrees F should see a doctor as a matter of urgency. Moreover, babies less than 12 weeks old should be seen if there is any fever, no matter the temperature.

Never treat flu in children or teens (or any viral illness involving fever) with aspirin as this can lead to a potentially life-threatening condition known as Reye's syndrome.

Congestion

Congestion is usually not a major ​concern when you have a cold or flu, but there are times when persistent or severe congestion needs to be looked at by a doctor. In adults or children, even a simple cold that doesn't resolve can lead to a secondary infection such as sinusitis, acute bronchitis (chest cold), or pneumonia.

Most colds clear up in seven to 10 days. Those that last longer should be always a cause for concern, especially in children. With regards to congestion, runny nose and nasal congestion are more common with colds than with flu, both of which increase the risk of sinusitis.

According to the CDC, you should seek immediate medical attention if congestion persists for more than 10 days or is accompanied by any of the following symptoms:

Children three months and under with a fever over 100.4 degrees F should be taken to the emergency room without exception or delay.

Even if symptoms are not severe, you should see a doctor if they persist for more than three weeks or recur. These include having a persistent cough (with or without discharge), chest pain or soreness, sore throat, body aches, or persistent fatigue.

Cough

Coughs from colds and flu tend to be annoying at best, but there are times when they are warning signs of something serious. Broadly speaking, you should be concerned if a cough:

  • Is persistent or getting worse
  • Is interfering with breathing
  • Brings up excessive or abnormal mucus or phlegm

In children, you should seek immediate medical care if confronted with the following symptoms:

With adults, a cough warrants urgent medical care when there is:

  • Coughing or fever that improves but suddenly worsens or returns
  • Bloody mucus
  • Difficulty breathing
  • Shortness of breath
  • Persistent pain or pressure in the chest
  • Severe weakness
  • Persistent dizziness or confusion

The U.S. Food and Drug Administration (FDA) advises against the use of over-the-counter cough and cold medications in children under 2 due to safety concerns and the lack of proven efficacy.

Sore Throat

Doctor examining patients throat in doctors office
Martin Barraud / Getty Images

If your throat hurts so badly that you cannot swallow, you need to see a doctor. Although pharyngitis (sore throat) is common with both colds and flu, it should not be so bad that it interferes with your ability to eat, drink, or sleep.

Most sore throats should improve with rest and at-home treatment. However, a severe sore throat should be seen by a doctor if accompanied by a fever over 104 degrees F or if it is interfering with your ability to breathe while sleeping. Symptoms like these could be a sign of a secondary bacterial infection.

In cases of streptococcal infection (strep throat), a red skin rash may accompany throat soreness and pain.

Headache

Headaches are fairly common with colds and flu. With colds, they tend to occur when pressure builds in the sinuses and nasal passages. With the flu, headaches are often severe and tend to spread over the forehead and behind the eyes.

In most cases, headaches caused by a cold or flu will resolve on their own with the rest of the symptoms. A rare exception is a secondary infection known as encephalitis in which the flu virus infiltrates the brain and causes inflammation.

Influenza is a rare cause of secondary encephalitis, but its incidence seems to have increased after the 2009 H1N1 influenza A virus pandemic.

Symptoms of encephalitis include:

  • Severe headache
  • High fever
  • Nausea and vomiting
  • Extreme drowsiness
  • Loss of coordination
  • Extreme sensitivity to light

Encephalitis is always treated as a medical emergency.

Never use aspirin to treat headaches in children under 14 due to the risk of Reye's syndrome. Consider non-aspirin alternatives such as Tylenol (acetaminophen) or Advil (ibuprofen) instead.

Stomach Pain

Stomach pain is a less common symptom of colds and the flu, but it has become common with certain influenza subtypes like H1N1. With the H1N1 virus, abdominal pain is often accompanied by diarrhea and vomiting.

Influenza, a respiratory infection, should not be confused with gastroenteritis (stomach flu), the latter of which can be caused by viruses, bacteria, or parasites.

According to the CDC, persistent abdominal pain is an indication for urgent medical care in people with the flu.

Persistent or severe vomiting or diarrhea can also lead to dehydration in which the body loses the fluids and electrolytes (like sodium and potassium) it needs to function normally.

Seek medical care if vomiting or diarrhea persists for more than 24 hours and is accompanied by signs of dehydration, including:

In children, seek emergency care if there:

  • Is no urine output in eight hours
  • Are no tears when crying
  • Is a general lack of alertness when awake

Note that Reye's syndrome can also cause abdominal pain. It typically starts with severe stomach pain as well as copious vomiting, lethargy, and confusion. Though Reye's syndrome is rare, it is a medical emergency that can lead to seizures and death if not treated quickly and appropriately. Reye's should be considered in children with the flu, chickenpox, and other fever-causing viral illnesses who receive aspirin.

11 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. People at high risk for flu complications.

  2. Centers for Disease Control and Prevention. Flu: What to do if you get sick.

  3. National Institute of Neurological Disorders and Stroke. Reye's syndrome information page.

  4. Centers for Disease Control and Prevention. Chest cold (acute bronchitis).

  5. U.S. Food and Drug Administration. When to give kids medicine for coughs and colds.

  6. American Osteopathic Society. Know the warning signs when to call the doctor if your sore throat persists.

  7. Al-Hamad AM. Streptococcal throat. Therapeutic options and macrolide resistanceSaudi Med J. 2015;36(9):1128-9. doi:10.15537/smj.2015.9.11987

  8. Meijer WJ, Linn FH, Wensing AM, et al. Acute influenza virus-associated encephalitis and encephalopathy in adults: a challenging diagnosisJMM Case Rep. 2016;3(6):e005076. doi:10.1099/jmmcr.0.005076

  9. Venkatesan A, Geocadin RG. Diagnosis and management of acute encephalitis: A practical approachNeurol Clin Pract. 2014;4(3):206-15. doi:10.1212/CPJ.0000000000000036

  10. Cleveland Clinic. Headache medications.

  11. Collins M, Claros E. Recognizing the face of dehydration. Nursing. 2011 Aug;41(8):26-21. doi:10.1097/01.NURSE.0000399725.01678.b7

By Kristina Duda, RN
Kristina Duda, BSN, RN, CPN, has been working in healthcare since 2002. She specializes in pediatrics and disease and infection prevention.