Laryngitis is most commonly caused by a viral infection, the same kind that gives you a cold or the flu. The resulting inflammation swells your vocal cords, making your voice hoarse, raspy, or sometimes barely audible. But viruses are only one piece of the picture. Depending on whether your laryngitis lasts a few days or lingers for weeks, the underlying cause can range from yelling at a concert to stomach acid creeping up your throat while you sleep.
Acute vs. Chronic: Why Duration Matters
Doctors split laryngitis into two categories based on how long it lasts. Acute laryngitis comes on suddenly and typically clears within one to two weeks. Chronic laryngitis persists beyond three weeks and often points to an ongoing irritant or underlying condition rather than a simple infection. The distinction matters because the causes, and what you need to do about them, are very different.
Viral Infections Are the Most Common Cause
The overwhelming majority of acute laryngitis cases trace back to a virus. The usual suspects include common cold viruses, influenza and parainfluenza (the same viruses behind croup in children), respiratory syncytial virus (RSV), and adenoviruses. COVID-19 also causes laryngitis, sometimes as a lingering symptom even after the initial infection resolves. Less commonly, measles, chickenpox, and whooping cough can inflame the larynx as part of their broader respiratory effects.
Because these are viral infections, antibiotics won’t help. The inflammation runs its course as your immune system fights off the virus, and your voice gradually returns to normal. Most people recover within 7 to 10 days with nothing more than rest, fluids, and avoiding whispering (which actually strains the vocal cords more than speaking softly).
Vocal Overuse and Strain
You don’t need a virus to inflame your vocal cords. Yelling, singing for extended periods, or even talking loudly for hours can do it. When you force your voice, the two vocal folds in your larynx press together with greater force than normal. That extra friction causes the contact area between the folds to swell, and swollen vocal cords vibrate differently, producing that characteristic hoarseness.
What makes vocal strain tricky is that it can become self-reinforcing. Once your voice starts to weaken, the natural instinct is to push harder to compensate. That extra effort creates even more swelling, which further degrades your voice and delays recovery. Teachers, singers, coaches, lawyers, referees, and construction workers who shout over machinery are all at elevated risk. Children who strain their voices during cheerleading or playground games can develop it too.
For people whose livelihoods depend on their voice, repeated episodes of vocal strain can tip into chronic laryngitis if the cords never get a chance to fully heal.
Acid Reflux and Laryngopharyngeal Reflux
Stomach acid doesn’t always stay in the stomach. In gastroesophageal reflux disease (GERD), acidic fluids travel backward into the esophagus. When that acid reaches all the way up to the throat and larynx, the condition is called laryngopharyngeal reflux, or LPR, and it’s one of the most common causes of chronic laryngitis.
The larynx is far more sensitive to acid than the esophagus. Two things appear to happen: the acid and digestive enzymes directly irritate the delicate tissue lining the larynx, and the presence of acid in the lower esophagus can trigger nerve reflexes that cause chronic throat clearing and coughing, which themselves damage the vocal cord lining over time. Many people with LPR don’t experience classic heartburn, so they never suspect reflux as the cause of their hoarseness. Symptoms like a persistent lump-in-the-throat sensation, morning hoarseness, or a chronic dry cough are more typical clues.
Smoking, Alcohol, and Chemical Irritants
Cigarette smoke is a potent laryngeal irritant. It causes swelling and inflammation that thickens the vocal cords over time, often lowering the pitch of the voice or giving it a harsh, raspy quality. Cigar smoke and marijuana smoke produce similar effects. Heavy alcohol use causes its own form of chemical irritation to the larynx, and the combination of smoking and drinking compounds the damage considerably.
Workplace and environmental exposures round out this category. Concentrated air pollutants like spray paints, oven cleaners, and industrial solvents can inflame the larynx with repeated exposure. Smoke inhalation during a fire and inhaling heated fumes (as with crack cocaine use) cause particularly acute damage. Even chronic exposure to dust in industrial settings is enough to sustain low-grade laryngeal inflammation indefinitely.
Bacterial and Fungal Infections
Bacterial laryngitis is far less common than the viral kind, but it does occur and tends to be more severe. Bacterial infections of the larynx sometimes develop as a secondary infection on top of a viral illness, when the initial inflammation creates an opening for bacteria to take hold. These cases are more likely to require medical treatment.
Fungal laryngitis is rare in healthy people but can affect those with weakened immune systems, such as people on long-term inhaled corticosteroids for asthma, those undergoing chemotherapy, or individuals with HIV. If you use a steroid inhaler and notice persistent hoarseness, rinsing your mouth after each use helps prevent fungal growth in the throat and larynx.
Medications That Mimic Laryngitis
Some medications cause hoarseness that looks and feels like laryngitis even though no inflammation is present. Antihistamines, cough suppressants, diuretics, and certain psychiatric medications can excessively dry out the throat, making the voice sound rough. Decongestants and some blood pressure medications thicken the mucus in your throat, which interferes with how the vocal cords vibrate. If your hoarseness started around the same time as a new medication, the drug itself may be the culprit rather than an infection or irritant.
Autoimmune and Systemic Diseases
A number of autoimmune conditions can affect the larynx, though these causes are uncommon. Rheumatoid arthritis can impair movement of the small joints that control the vocal cords, causing hoarseness and sometimes a sensation of throat tightness. Sjögren’s syndrome dries out the mucous membranes throughout the body, including the larynx, leading to thick secretions and irregular vocal cord edges. Lupus can cause vocal cord inflammation and small nodules on the folds themselves.
Granulomatosis with polyangiitis (formerly called Wegener’s granulomatosis) is a rarer but notable cause. It involves inflammation of blood vessels and can produce narrowing below the vocal cords in 6 to 20 percent of patients. Roughly 41 percent of people with this condition report voice symptoms like hoarseness, cough, or throat pain. Other conditions with documented laryngeal effects include relapsing polychondritis (which can soften the cartilage of the larynx), myasthenia gravis (which weakens the muscles controlling the vocal folds), and multiple sclerosis (which impairs muscle coordination in the larynx).
These causes typically show up alongside other systemic symptoms, so isolated hoarseness is unlikely to be the first sign of an autoimmune disease. But for someone already diagnosed with one of these conditions, vocal changes are worth mentioning to a doctor.
Other Contributing Factors
Chronic sinusitis with postnasal drip can irritate the larynx as mucus constantly drains across it. Allergies produce a similar effect, with the added issue of frequent throat clearing that batters the vocal cords. Prior surgery involving intubation (having a breathing tube placed in the throat for anesthesia) can injure the vocal cords directly, causing hoarseness that may take days or weeks to resolve, and occasionally longer if scarring develops.
Age also plays a role. As you get older, the vocal cords lose muscle mass and elasticity, making them more susceptible to irritation and slower to recover from any of the causes listed above. This is why a bout of laryngitis that would resolve in a few days for a 25-year-old might linger for two weeks in someone over 60.