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15 Common Symptoms of Pneumonia

9 min read

By Emily Lockhart

Medically Reviewed by Dr. Gerald Morris

Pneumonia is a type of lung, or respiratory, infection that begins with an innocent cough, but then turns into a sudden high fever with labored breathing. For most people, pneumonia is treatable with prescription medication (e.g., antibiotics), with all symptoms vanishing in a few weeks. However, for babies, seniors, and those with other medical conditions, a bout of pneumonia can mean hospitalization with serious symptoms.

Here’s a look at the 15 most common symptoms of pneumonia…

1. Cough

Pneumonia is a type of lung infection that can strike one or both lungs. The source of the infection can be bacterial, fungal, or viral in nature, but fluid will typically settle into the lungs air sacs, or alveoli, causing breathing difficulties and inevitably a severe cough. This is why a flu- or cold-like cough is often noticeable in the beginning stages of pneumonia and that cough is typically accompanied by thick green mucus, which may indicate infection.

Untreated pneumonia will worsen and so will the related cough. The severity of the cough and mucus depends on the cause of the inflammation (meaning if the organism causing the infection is bacterial, fungal, or viral in nature). Other factors will also play into the severity of pneumonia for different individuals. For instance, immune strength can differ due to age (elderly and young children are usually more at risk for severe symptoms and hospitalization). Also, general health can impact pneumonia severity, and those with compromised immunity are most at risk.

2. Fever

Pneumonia is an inflammatory infection of the lungs, and the infection can be fungal, bacterial, or viral. However, as with most infections, pneumonia will typically present with a high fever. A high fever may develop, particularly in babies, small children, and those with other medical conditions, due to weakened or compromised immunity, which means those individuals are less able to fight off the infection as quickly and effectively as healthy individuals.

As mentioned, a fever that accompanies pneumonia is typically high, rising up to 40.9-degrees Celsius or 105-degrees Fahrenheit as the infection worsens. Most pneumonia cases that begin with the flu (referred to as influenza pneumonia), can last anywhere from 2 to 3 weeks after becoming infected. If you develop a fever and suspect pneumonia, please seek medical attention immediately.

3. Chills

Chills are a common symptom of both the flu and pneumonia. However, the severity of symptoms is typically a good indicator. It’s very typical for patients with pneumonia to develop the infection due to catching the flu, with milder symptoms, such as congestion, cough, and sore throat at the start. However, as the infection travels down into the lungs, more severe symptoms, including chills, will develop.

The severity of your pneumonia will depend on the cause, which can be viral (developing due to a virus such as the influenza virus [or the flu], human metapneumovirus, adenovirus, or respiratory syncytial virus (RSV). Bacterial pneumonia, is caused by bacteria such as Streptococcus pneumoniae, which results in illness more severe as compared to those with viral pneumonia. In the case of bacterial pneumonia, antibiotics are typically prescribed to help fight the infection.

4. Labored Breathing

Pneumonia is a lung infection that strikes the lung tissue with fluid and pus. Obviously, an infection of this nature that develops in the lungs can make it rather difficult for oxygen transportation from the lungs air sacs (or the alveoli) to the bloodstream. This is why a prime indicator of pneumonia for doctors is breathing difficulty, which is usually accompanied by fever and cough.

Any infection (be it viral, fungal, or bacterial) that sets into the lungs will result in labored or restricted breathing. This further taxes the lungs and can also result in pain, tightness, and pressure in the chest or abdomen. Wheezing and shortness of breath can also cause breathing to become rapid and shallow in nature.

5. Chest Pain

Due to the nature of pneumonia (a lung infection that causes fluid or pus buildup, and obstructs oxygen flow between the alveoli [the lung’s air sacs] and the bloodstream), chest pain can also be a common symptom, with labored breathing causing chest and even abdominal pain and tightness.

Pneumonia is typically viral (which means it’s caused by a virus such as influenza, or the flu), fungal (which means it’s caused by a fungus invading the lungs), or bacterial (which means a bacteria such as Streptococcus pneumoniae causes the infection). Depending on the cause of infection and its severity (for instance pneumonia can strike one or both lungs  with [“double pneumonia”], worsening cough, mucus build up, and labored breathing can result in more severe pain in the chest walls.

6. Increased Heart Rate

When the body suffers infection or labored breathing, the heart rate will increase, which is often the case with pneumonia. A study from the University of Texas Health Science Center, located in San Antonio, Texas, examined the cardiac problems that developed after patients were hospitalized for pneumonia. Findings showed that patients hospitalized for the infection were at increased risk for the development of irregular heartbeat (arrhythmia), heart attack, stroke, and heart disease.

The data showed that an irregular heart beat (caused by a lung infection) can increase the risk of long-term irregular heartbeat and cardiovascular disease if patients were not monitored for heart issues and treated quickly. The good news is that if you enter the hospital with an irregular heartbeat due to pneumonia, if it’s detected and treated early with medication, heart issues can be prevented in the future.

7. Fatigue

Feelings of exhaustion or weakness often accompany pneumonia. Depending on the cause of the lung infection (viral, bacterial, or fungal), the fatigue you experience can differ vastly depending on your age, immune strength, and severity of your symptoms. For instance, young children and seniors often experience more severe symptoms along with those with compromised immunity due to another health condition (i.e., HIV). Those individuals may need hospitalization and antibiotic medication in order to fight off the infection.

For the average healthy adult, the fatigue you experience will be related to how much energy it takes for your body to fight off the infection. Exhaustion can occur in as little as 3 days and last up to 2 weeks. However, during this time, if symptoms worsen, you should see a medical professional immediately. Those with weakened immunity may need treatment in a hospital, and fatigue (tiredness) from pneumonia can last up to a month or more.

8. Nausea

An irritated digestive system, and in severe cases, vomiting can occur with pneumonia if the infection is severe. According to the University of Maryland Medical Center, roughly 10 million are stricken with pneumonia annually in the United States. However, the severity of the lung infection varies depending on several factors, such as age, health, and lifestyle. Although most cases of pneumonia are treatable, between 40,000 and 700,000 individuals die each year due to pneumonia-related symptoms.

High risk individuals include older adults who live in nursing homes, hospitalized patients (particularly those on a ventilator), young children (who risk developing chronic obstructive pulmonary disease [COPD] in adulthood due to childhood pneumonia), pregnant women (due to lowered immunity and increased labor complications), and those with compromised immune health (including cancer, diabetes, and AIDS patients).

9. Diarrhea

Pneumonia often irritates the digestive system and causes loose stool or diarrhea. According to several leading health experts, pneumonia and other lung infections and conditions can cause pressure and breathing restrictions that affect the chest. Many patients who’ve dealt with pneumonia report a type of indigestion and stomach upset that presents similarly to heartburn (or a burning pain in the center of the chest that radiates outward). However, with pneumonia eating may not be the cause for stomach upset and heartburn-like symptoms.

Pneumonia is one health condition that’s unrelated to digestive problems yet oftentimes displays heartburn-like symptoms, stomach upset, nausea, vomiting, and diarrhea. If stomach upset and diarrhea persist, you run the risk of becoming dehydrated. Please see a doctor immediately if these types of symptoms worsen instead of improve.

10. Bloody Mucus

In severe cases, blood may appear in mucus as congestion and cough worsen with pneumonia. Hemoptysis (or coughing up blood) is the term doctors use to characterize bloody mucus from the respiratory tract (the lungs and throat). When patients with pneumonia cough up blood, it appears differently than what bleeding from the mouth, throat, or gastrointestinal tract would look like. For instance, most cases of pneumonia will present with bloody mucus that appears bubbly, which is due to the blood mixing with mucus and oxygen.

Blood tinged mucus can range in color in pneumonia patients. For instance, some characterize it as rust colored, orange tinged, or bright red. No matter what the quantity or color, it’s vital to seek immediate medical attention if your mucus contains any trace of blood within. Even in cases where mucus only contains streaks of blood, you should seek medical attention for possible pneumonia immediately.

11. Delirium, Confusion, or Changes in Mental Awareness

As pneumonia is a condition that causes inflammation and infection, it’s possible for it to interfere with brain function and possibly lead to delirium, which defines as “an abrupt change in the brain that causes mental confusion and emotional disruption.”

Such confusion—which may also be the result of a high fever or lack of oxygen in the blood—is particularly common in adults with pneumonia that are 65 years of age or older, and they may become disoriented or lack awareness of what’s going on around them.

12. Low Body Temperature

In some cases when people are suffering from pneumonia, they may experience having a body temperature that is lower than normal instead of a fever. Like delirium and confusion, this is particularly common in adults over the age of 65, as well as in those with weak immune systems.

For the elderly, this is often due to their body’s reduced ability to regulate its temperature, especially when dealing with infection. But it may also be due to the infections themselves lowering the body’s temperature in an effort to stay alive, as a fever will kill off the virus or bacteria.

13. Sweating

As mentioned earlier, a high fever is a common symptom of pneumonia, often increasing the body’s temperature up to 105-degrees Fahrenheit (40.9-degrees Celsius). This is how the body fights off an infection, so a reasonable fever is actually a good thing in this case.

But because the body is several degrees warmer than normal, it is not uncommon for someone with pneumonia to sweat (sometimes profusely) as the body attempts to cool off and keep from dangerously overheating. indicates that this is a particularly common symptom in those who are suffering from bacterial pneumonia.

14. Purplish Skin, Lips, and Fingernails

Pneumonia may also cause the skin to take on a “dusky or purplish skin color,” as described by It may be most noticeable on areas of the body such as the lips and fingernails.

This change in skin color is a condition known as cyanosis, and is “usually caused by low oxygen levels in the red blood cells or problems getting oxygenated blood to your body,” says Cyanosis occurs in people with pneumonia because inflamed air sacs (alveoli) in the lungs make it hard to breathe and, therefore, get a sufficient amount of oxygen into the body. As with sweating, the source indicates this symptom is particularly common in cases of bacterial pneumonia.

15. Weight Loss

People with pneumonia may also experience weight loss over the course of the infection. This is largely dependent on the severity of pneumonia, but in some cases says, “…pneumonia can overburden the system, which causes the person to become worn down and de-conditioned.” This decline in a person’s health can cause a loss of appetite, which results in weight loss.

Loss of appetite can also occur due to changes in metabolism because of the infection, as well as chest pain and a low level of physical activity. It may also result from taking certain antibiotics, as they can affect the taste of food.

MD, Family Medicine, Internal Medicine

Gerald Morris, MD is a family medicine/internal medicine physician with over 20 years expertise in the medical arena. Dr. Morris has spent time as a clinician, clinical research coordinator/manager, medical writer, and instructor. He is a proponent of patient education as a tool in the diagnosis and treatment of acute and chronic medical conditions.

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