Acute Bronchitis: Symptoms, Causes & When to See a Doctor

What Is Acute Bronchitis?

Acute bronchitis is a temporary inflammation of the bronchial tubes—the airways that carry air to and from your lungs. It causes a persistent cough, often with mucus, and typically develops following a cold or other upper respiratory infection. Unlike chronic bronchitis, acute bronchitis usually resolves completely within 2-4 weeks.

The bronchial tubes are the main airways in your lungs. When these airways become inflamed due to infection, the lining swells and produces excess mucus. This inflammation triggers your body's natural reflex to clear the airways through coughing, which is why a persistent cough is the hallmark symptom of bronchitis.

Acute bronchitis is one of the most common respiratory conditions worldwide, affecting approximately 5% of adults each year. It is sometimes called a "chest cold" because it often develops after a common cold or upper respiratory infection. The condition occurs in both children and adults, although it tends to be more common during fall and winter months when respiratory viruses are most prevalent.

Understanding the difference between acute and chronic bronchitis is important. Acute bronchitis is a short-term condition that develops suddenly and resolves completely, usually without any lasting damage to the airways. Chronic bronchitis, on the other hand, is a long-term condition classified as a type of Chronic Obstructive Pulmonary Disease (COPD), characterized by a productive cough lasting at least three months per year for two consecutive years. Chronic bronchitis is typically caused by long-term smoking and requires ongoing medical management.

How bronchitis affects your airways

When viruses or bacteria enter your respiratory system, they can infect the cells lining your bronchial tubes. Your immune system responds by sending white blood cells to fight the infection, which causes inflammation. The inflamed bronchial lining swells, narrowing the airways and producing excess mucus as a protective mechanism.

This process creates the classic symptoms of bronchitis: coughing to expel mucus, chest discomfort from the inflammation, and sometimes wheezing or shortness of breath if the airways become significantly narrowed. The mucus your body produces is actually helping to trap and remove infectious particles from your airways, which is why coughing up phlegm is an important part of recovery.

What Are the Symptoms of Acute Bronchitis?

The main symptoms of acute bronchitis include a persistent cough (initially dry, then producing mucus), chest discomfort or soreness when coughing, fatigue, and mild fever. Symptoms typically begin after a cold and may include wheezing or shortness of breath. The cough can last 2-3 weeks, sometimes longer.

Acute bronchitis often begins with symptoms similar to a common cold, such as a runny nose, sore throat, and general fatigue. Within a few days, a cough develops that becomes the predominant symptom. Initially, the cough is often dry and irritating, but it typically transitions to a productive cough with mucus after a few days.

The mucus produced during bronchitis can vary in color from clear or white to yellow, green, or even brownish. While many people believe that colored mucus indicates a bacterial infection requiring antibiotics, this is a common misconception. The color of mucus is influenced by the presence of white blood cells and other immune cells fighting the infection, regardless of whether the cause is viral or bacterial.

Common symptoms of acute bronchitis

The presentation of acute bronchitis varies from person to person, but most individuals experience a combination of the following symptoms. The cough is universally present and is often the most bothersome symptom, particularly when it disrupts sleep at night.

• Persistent cough: Initially dry, becoming productive with mucus over time
• Mucus production: Clear, white, yellow, green, or brown phlegm
• Chest discomfort: Soreness or tightness, especially when coughing
• Fatigue: General tiredness and low energy levels
• Low-grade fever: Usually below 38°C (100.4°F)
• Body aches: Mild muscle or joint pain
• Sore throat: Often present early in the illness
• Runny or stuffy nose: Common if bronchitis follows a cold

Symptoms that may indicate airway involvement

When bronchitis causes significant inflammation or produces excessive mucus, you may experience symptoms related to airway narrowing. These symptoms are more common in individuals with underlying conditions like asthma or in smokers, but they can occur in anyone with more severe inflammation.

Wheezing—a high-pitched whistling sound when breathing—occurs when air passes through narrowed airways. This is caused by inflammation and mucus partially blocking the bronchial tubes. Similarly, shortness of breath may occur, particularly during physical activity, as the airways' reduced capacity limits airflow.

In most healthy individuals, these symptoms are mild and temporary. However, if you experience significant difficulty breathing, severe wheezing, or your symptoms are progressively worsening, you should seek medical attention promptly.

When cough lingers after recovery

One of the most common concerns patients have is a cough that persists even after they otherwise feel better. This is completely normal and expected with acute bronchitis. The cough may continue for 2-4 weeks after other symptoms have resolved, and in some cases, it can persist for up to 8 weeks.

This lingering cough occurs because the bronchial lining needs time to fully heal from the inflammation. Even after the infection is cleared, the airways remain sensitive and hyperreactive, triggering coughs in response to irritants like cold air, dust, or physical exertion. Rest assured that this gradual improvement is typical, but if your cough lasts beyond 4 weeks without improvement, consult a healthcare provider.

What Causes Acute Bronchitis?

Acute bronchitis is caused by viral infections in approximately 90% of cases, with the same viruses responsible for colds and flu being the most common culprits. Bacterial infections account for less than 10% of cases. Risk factors include smoking, weakened immunity, air pollution exposure, and pre-existing respiratory conditions.

Understanding the causes of acute bronchitis is essential, particularly because it explains why antibiotics are usually not recommended for treatment. The vast majority of acute bronchitis cases are caused by viruses that your immune system must fight on its own—antibiotics cannot kill viruses and will not speed your recovery from a viral infection.

Viral infections

Viruses cause the overwhelming majority of acute bronchitis cases. These are the same respiratory viruses that cause common colds, influenza, and other upper respiratory infections. When these viruses spread down from the upper respiratory tract into the bronchial tubes, bronchitis develops.

Common viruses that cause acute bronchitis include rhinovirus (the most common cause of the common cold), influenza A and B (flu viruses), respiratory syncytial virus (RSV), adenovirus, and coronavirus (including SARS-CoV-2, the virus causing COVID-19). These viruses spread easily through respiratory droplets when an infected person coughs, sneezes, or talks, or through contact with contaminated surfaces.

Bacterial infections

Bacterial bronchitis is relatively uncommon, accounting for less than 10% of cases. When bacteria do cause bronchitis, it is often a secondary infection—meaning bacteria take advantage of airways already weakened by a viral infection. The most common bacteria involved include Mycoplasma pneumoniae, Chlamydophila pneumoniae, and Bordetella pertussis (the cause of whooping cough).

In some cases, bacteria like Streptococcus pneumoniae or Haemophilus influenzae—which more commonly cause pneumonia—may infect the bronchial tubes. Bacterial bronchitis is more likely in people with weakened immune systems, those with chronic lung diseases, and individuals who smoke.

Risk factors for acute bronchitis

While anyone can develop acute bronchitis, certain factors increase your risk of both developing the condition and experiencing more severe symptoms. Understanding these risk factors can help you take preventive measures.

• Smoking: Cigarette smoke damages the bronchial lining and impairs the airways' natural defenses, making smokers significantly more susceptible to respiratory infections
• Weakened immune system: Conditions or medications that suppress immune function increase vulnerability to infections
• Gastroesophageal reflux disease (GERD): Stomach acid irritating the throat and airways can increase bronchitis risk
• Exposure to air pollution: Air pollutants and industrial irritants can damage airways and trigger inflammation
• Pre-existing lung conditions: People with asthma or COPD are more prone to bronchitis
• Age: Very young children and older adults have higher susceptibility
• Occupational exposure: Workers exposed to dust, chemicals, or fumes have increased risk

What Can I Do at Home to Feel Better?

Home care for acute bronchitis focuses on rest, staying well-hydrated, using honey for cough relief (for adults and children over 1 year), and managing symptoms with over-the-counter medications if needed. Using a humidifier and avoiding irritants like smoke can also help ease symptoms while your body heals.

Since most cases of acute bronchitis are caused by viruses and will resolve on their own, home care focuses on supporting your body's natural healing process while minimizing discomfort. The cough and mucus production are actually helpful—they work to clear the infection from your airways—so the goal is to manage symptoms rather than completely suppress them.

Rest and stay home

Rest is crucial for recovery from acute bronchitis. When you're sick, your body is working hard to fight the infection, and physical rest allows your immune system to focus its energy on healing. Avoid strenuous activities and take time off from work or school if possible, particularly during the first few days when symptoms are most severe.

Staying home when you're sick also serves an important public health function: it prevents you from spreading the infection to others. Since the viruses that cause bronchitis spread easily through respiratory droplets, staying home until you feel better helps protect your family, coworkers, and community.

Stay well hydrated

Drinking plenty of fluids is one of the most important things you can do to feel better and recover faster. Adequate hydration helps thin the mucus in your airways, making it easier to cough up. Thinner mucus is less likely to block your airways and creates less chest congestion.

Aim for at least 8-10 glasses of fluid per day. Water is ideal, but warm beverages like herbal tea, clear broth, and warm water with lemon can be particularly soothing. Warm liquids also have a mild soothing effect on irritated airways. Avoid alcohol and caffeine, which can cause dehydration and potentially worsen symptoms.

Use honey for cough relief

Honey has been shown in clinical studies to be effective for cough relief and may work as well as some over-the-counter cough medicines. Taking 1-2 teaspoons of honey before bedtime can help soothe your throat and reduce coughing that disrupts sleep. You can take honey directly or mix it into warm tea or water.

Use a humidifier

Adding moisture to the air with a cool-mist humidifier can help ease coughing and loosen congestion in your chest. Dry air can irritate already-inflamed airways and make coughing worse. Keep the humidity level between 40-50% for optimal comfort, and be sure to clean your humidifier regularly to prevent mold and bacteria growth.

If you don't have a humidifier, spending time in a steamy bathroom—such as sitting near a hot shower—can provide temporary relief. Breathing in warm, moist air helps soothe irritated airways and loosens mucus.

Over-the-counter medications

While there is limited evidence that over-the-counter cough medicines provide significant benefit for acute bronchitis, some people find relief from certain products. Here's what the evidence shows:

• Pain relievers and fever reducers: Acetaminophen (paracetamol) or ibuprofen can help relieve fever, headache, and body aches associated with bronchitis
• Cough suppressants: Products containing dextromethorphan may help reduce a dry, irritating cough, particularly at night. Evidence for effectiveness is limited
• Expectorants: Guaifenesin may help thin mucus, though drinking plenty of fluids is equally effective
• Menthol products: Vapor rubs and cough drops containing menthol may provide temporary relief by creating a cooling sensation

Be cautious with combination cold medicines that contain multiple ingredients, as they may include medications you don't need. Always read labels carefully, follow dosing instructions, and consult a pharmacist if you're unsure which product is appropriate for you.

When Should I See a Doctor for Bronchitis?

Most acute bronchitis cases don't require medical care. See a doctor if you have fever above 38°C (100.4°F) lasting more than 3 days, blood in your mucus, significant difficulty breathing, symptoms worsening after initial improvement, or a cough lasting more than 3 weeks. Seek emergency care for severe breathing difficulty or chest pain.

The vast majority of people with acute bronchitis will recover fully without needing to see a doctor. However, there are specific warning signs and circumstances where medical evaluation is important to rule out more serious conditions like pneumonia or to address bacterial infections that may benefit from treatment.

Warning signs that require medical attention

Contact a healthcare provider if you experience any of the following symptoms, as they may indicate a more serious condition or a complication that requires treatment:

• High or prolonged fever: Temperature above 38°C (100.4°F) lasting more than 3 days
• Blood in mucus: Coughing up blood or rust-colored sputum
• Breathing difficulties: Significant shortness of breath or wheezing
• Worsening symptoms: Symptoms that improve then suddenly worsen
• Prolonged illness: Cough lasting more than 3 weeks without improvement
• Recurrent bronchitis: Frequent episodes of bronchitis
• Chills and sweating: Severe chills or night sweats

People who should consult a doctor early

Certain groups of people should seek medical advice sooner rather than later when they develop symptoms of bronchitis. These individuals have a higher risk of complications or may need closer monitoring during their illness:

• People with chronic lung conditions: Those with asthma, COPD, or other respiratory diseases
• Immunocompromised individuals: People with weakened immune systems due to disease or medication
• Heart disease patients: Those with heart failure or other cardiovascular conditions
• Older adults: People over 65 years old, especially those with other health conditions
• Infants and young children: Especially if breathing difficulties develop
• Pregnant women: If symptoms are severe or concerning

How Is Acute Bronchitis Diagnosed?

Acute bronchitis is usually diagnosed based on your symptoms and a physical examination. Your doctor will listen to your lungs with a stethoscope for abnormal sounds like wheezing. Chest X-rays may be ordered to rule out pneumonia, and occasionally sputum tests or blood tests are needed for more severe or prolonged cases.

In most cases, diagnosing acute bronchitis is straightforward and doesn't require extensive testing. Your doctor will ask about your symptoms, their duration, and any underlying health conditions, then perform a physical examination to assess your breathing and look for signs of complications.

Physical examination

During the physical exam, your doctor will listen to your lungs using a stethoscope. In bronchitis, they may hear wheezing—a whistling sound—or coarse breath sounds caused by mucus in the airways. They will also check your throat for redness or swelling, feel for swollen lymph nodes in your neck, and may examine your ears and sinuses to rule out other infections.

Your doctor will also assess your overall condition, including checking your temperature, breathing rate, and oxygen levels (using a pulse oximeter that clips on your finger). These vital signs help determine the severity of your illness and whether additional testing or treatment is needed.

Additional tests

For uncomplicated acute bronchitis in otherwise healthy adults, additional testing is usually unnecessary. However, your doctor may order tests in certain situations:

• Chest X-ray: May be ordered to rule out pneumonia if you have high fever, severe symptoms, abnormal lung sounds, or if symptoms persist longer than expected
• Sputum culture: Analysis of your mucus may be performed if bacterial infection is suspected or if you have a weakened immune system
• Blood tests: May be ordered to check for signs of severe infection or to rule out other conditions
• Pulmonary function tests: Sometimes performed if asthma is suspected or for people with recurrent bronchitis
• COVID-19 test: May be recommended depending on your symptoms and local guidelines

Distinguishing bronchitis from other conditions

Your doctor will also consider whether your symptoms might be caused by something other than acute bronchitis. Conditions that can produce similar symptoms include pneumonia (which is more severe and often requires antibiotics), asthma exacerbation, COPD flare-up, allergies, gastroesophageal reflux (GERD), or rarely, more serious conditions like lung cancer or heart failure.

How Is Acute Bronchitis Treated?

Most acute bronchitis cases require only supportive care—rest, fluids, and symptom management. Antibiotics are not recommended for routine bronchitis since 90% of cases are viral. Bronchodilators may be prescribed for people with significant wheezing. Treatment focuses on managing symptoms while your body clears the infection naturally.

The treatment of acute bronchitis centers on supportive care while your immune system fights the infection. Since the vast majority of cases are caused by viruses that cannot be treated with medications, the focus is on managing symptoms and allowing time for recovery.

Why antibiotics usually aren't needed

One of the most important things to understand about acute bronchitis treatment is that antibiotics are rarely appropriate. Despite being commonly requested by patients, antibiotics provide no benefit for viral infections and can actually cause harm through side effects and contribution to antibiotic resistance.

Multiple large-scale studies and systematic reviews, including Cochrane Reviews, have consistently found that antibiotics do not significantly speed recovery from acute bronchitis or reduce the duration of cough. International guidelines from organizations like the European Respiratory Society (ERS), American Thoracic Society (ATS), and World Health Organization (WHO) all recommend against routine antibiotic use for acute bronchitis.

Antibiotics may be considered in specific situations: when there is strong evidence of bacterial infection (which is rare), in patients with significant underlying chronic lung disease like COPD, in immunocompromised individuals, or when symptoms are unusually severe or prolonged. Your doctor will make this determination based on your individual circumstances.

Medications that may help

While there is no medication that cures acute bronchitis, several treatments can help manage specific symptoms:

• Bronchodilators: Inhaled medications (like albuterol/salbutamol) may be prescribed for patients with significant wheezing or shortness of breath, as they help relax and open the airways
• Pain relievers/fever reducers: Acetaminophen or ibuprofen can relieve headaches, body aches, and reduce fever
• Prescription cough suppressants: Medications containing codeine may occasionally be prescribed for severe, disruptive cough that interferes with sleep, though evidence for effectiveness is limited

Treatment for people with underlying conditions

If you have an underlying respiratory condition like asthma or COPD, acute bronchitis may trigger a flare-up of your chronic condition. In these cases, you may need to increase your regular medications or use rescue inhalers more frequently. Your doctor may also prescribe a short course of oral corticosteroids to reduce airway inflammation.

People with chronic conditions should follow their established action plans and contact their healthcare provider early if bronchitis symptoms develop, as they may need closer monitoring and more proactive treatment.

What Are the Possible Complications?

In most healthy people, acute bronchitis resolves without complications. However, bronchitis can occasionally progress to pneumonia, especially in smokers, older adults, or those with weakened immunity. Repeated episodes of bronchitis can contribute to developing chronic bronchitis. Seek medical care if symptoms worsen or don't improve.

While acute bronchitis is generally a self-limiting condition that resolves without long-term consequences, certain complications can occur, particularly in higher-risk individuals. Understanding these potential complications helps you know when to seek additional medical care.

Pneumonia

The most significant complication of acute bronchitis is pneumonia, an infection that spreads to the lung tissue itself (alveoli) rather than just the airways. Pneumonia is more serious than bronchitis and often requires antibiotic treatment. Warning signs that bronchitis may be developing into pneumonia include worsening symptoms after initial improvement, high fever, shaking chills, shortness of breath, or sharp chest pain when breathing.

Risk factors for developing pneumonia from bronchitis include advanced age, smoking, chronic lung disease, weakened immune system, and heart disease. If you fall into these categories and develop bronchitis, monitor your symptoms closely and don't hesitate to seek medical attention if you're concerned.

Chronic bronchitis and COPD

While a single episode of acute bronchitis doesn't cause chronic bronchitis, repeated episodes of bronchitis—particularly in people who smoke—can contribute to permanent airway damage and the development of chronic bronchitis or COPD. If you experience frequent bronchitis infections (several times a year), this is an important warning sign that should be evaluated by a healthcare provider.

For smokers, recurring bronchitis is often an early sign that smoking is damaging the airways. This is one of the most compelling reasons to quit smoking, as continuing to smoke dramatically increases the risk of developing permanent lung disease.

How Can I Prevent Acute Bronchitis?

Prevent acute bronchitis by washing hands frequently, avoiding close contact with sick people, getting vaccinated against flu and COVID-19, not smoking, and maintaining a healthy lifestyle. If you have asthma or COPD, keeping your condition well-controlled also helps prevent bronchitis episodes.

Since acute bronchitis is primarily caused by the same viruses responsible for colds and flu, prevention strategies focus on reducing your exposure to these viruses and strengthening your body's defenses against infection.

Hand hygiene and respiratory etiquette

The single most effective way to prevent respiratory infections, including bronchitis, is frequent handwashing. Wash your hands thoroughly with soap and water for at least 20 seconds, especially after being in public places, before eating, and after touching your face. If soap and water aren't available, use an alcohol-based hand sanitizer.

Avoid touching your face—particularly your eyes, nose, and mouth—as this is how viruses often enter your body. When you cough or sneeze, cover your mouth and nose with a tissue or your elbow, not your hands, to prevent spreading germs to surfaces you touch.

Vaccinations

While there is no vaccine specifically for bronchitis, several vaccines can help prevent respiratory infections that lead to bronchitis:

• Annual flu vaccine: Influenza commonly causes bronchitis; getting vaccinated each year significantly reduces your risk
• COVID-19 vaccine: Staying current with COVID-19 vaccinations helps prevent coronavirus infections that can cause bronchitis
• Pneumococcal vaccine: Recommended for older adults and high-risk individuals, this vaccine helps prevent bacterial pneumonia
• Pertussis (whooping cough) vaccine: Included in the Tdap booster, this helps prevent a bacterial cause of bronchitis

Lifestyle factors

A healthy lifestyle strengthens your immune system and makes you more resistant to infections:

• Don't smoke: Smoking damages your airways' natural defenses and dramatically increases bronchitis risk; if you smoke, quitting is the single best thing you can do for your respiratory health
• Exercise regularly: Moderate physical activity boosts immune function
• Eat a balanced diet: Adequate nutrition supports immune health
• Get enough sleep: Sleep deprivation weakens immune defenses
• Manage stress: Chronic stress can impair immune function
• Avoid air pollution: When possible, limit exposure to polluted air and industrial irritants