Most sore throats are caused by a viral infection, like a cold or the flu. Viruses account for 50% to 80% of all cases of acute pharyngitis, making them by far the most common culprit. The soreness typically resolves on its own within three to ten days without any specific treatment. But viruses aren’t the only explanation. Bacterial infections, environmental irritants, and even stomach acid can all make your throat hurt.
Viral and Bacterial Infections
The common cold is the single most frequent cause of a sore throat. Other viral causes include the flu, COVID-19, and mononucleosis (sometimes called “mono” or the “kissing disease”). With these infections, the sore throat usually arrives alongside other symptoms: a runny nose, cough, body aches, or fatigue. Mono tends to produce a more severe and longer-lasting sore throat, often accompanied by swollen glands and extreme tiredness that can persist for weeks.
Bacteria cause roughly 20% to 50% of sore throats overall, and the most important one to know about is group A strep. Strep throat accounts for 5% to 15% of sore throats in adults and 20% to 30% in children. It tends to come on suddenly with intense throat pain, fever, and swollen lymph nodes, but typically without a cough or runny nose. That distinction matters because strep requires antibiotics to clear the infection and prevent rare but serious complications like rheumatic fever. If your doctor confirms strep with a rapid test or throat culture, the standard treatment is a 10-day course of penicillin or amoxicillin.
What Makes Your Throat Actually Hurt
When a virus or bacterium infects your throat tissue, your immune system launches an inflammatory response. Infected cells release chemical signals, primarily prostaglandins and bradykinin, that do two things at once. They increase blood flow and cause tissue swelling (which helps immune cells reach the area), and they directly stimulate pain nerve endings in the throat lining.
Bradykinin is especially potent. It activates pain receptors and also makes blood vessels more permeable, leading to the swollen, raw feeling you notice when you swallow. Prostaglandins, meanwhile, sensitize temperature-sensing receptors in your throat so that they fire at normal body temperature, essentially turning your body’s own heat into a pain trigger. This is why your throat can feel like it’s burning even when you don’t have a fever. It’s also why anti-inflammatory pain relievers, which block prostaglandin production, work so well for sore throat pain.
Your immune system also releases cytokines, signaling molecules that spread beyond the throat and cause the general “sick feeling” of fever, fatigue, and low mood that often accompanies a sore throat.
Non-Infectious Causes
If your throat is sore but you don’t feel sick, the cause may not be an infection at all. Several environmental and medical conditions can produce the same scratchy, irritated feeling.
- Dry air: Low humidity, especially during winter when indoor heating runs constantly, dries out the mucous membranes lining your throat. You’ll notice this most in the morning after breathing dry air all night.
- Postnasal drip: Allergies, sinus infections, and cold weather can all increase mucus production. When that excess mucus drains down the back of your throat, it irritates the tissue and causes soreness, frequent throat clearing, and a feeling of something stuck in your throat.
- Voice strain: Yelling at a concert, talking for hours, or even whispering for extended periods can inflame your vocal cords and the surrounding tissue.
- Irritants: Cigarette smoke, air pollution, and chemical fumes can all cause throat irritation, particularly with repeated or prolonged exposure.
Silent Reflux: The Overlooked Cause
If your sore throat keeps coming back or never fully goes away, stomach acid may be the problem. Laryngopharyngeal reflux, often called “silent reflux,” occurs when acid travels all the way up from your stomach into your throat. Unlike typical acid reflux, you might not experience heartburn or indigestion at all, which is what makes it tricky to identify.
The hallmark symptoms are chronic hoarseness, a persistent need to clear your throat, a sensation of a lump in the throat, and mild but ongoing soreness. About 10% of people who visit a throat specialist end up being diagnosed with this condition. If you have chronic hoarseness, there’s roughly a 50% chance that silent reflux is the underlying cause. Treatment usually involves dietary changes, avoiding eating close to bedtime, and sometimes acid-reducing medication.
What Helps With the Pain
For a standard viral sore throat, the goal is comfort while your body clears the infection. Over-the-counter anti-inflammatory pain relievers are your best bet. In clinical trials, ibuprofen reduced sore throat pain by 80% within three hours, compared to 50% for acetaminophen at the same time point. By six hours, the gap widened further: ibuprofen still provided 70% relief while acetaminophen dropped to 20%. The reason for that difference ties back to the biology. Ibuprofen blocks prostaglandin production directly, tackling both pain and inflammation, while acetaminophen primarily works on pain perception without reducing swelling.
Cold liquids, ice chips, and throat lozenges can also provide temporary relief. Cold activates specific receptors in your throat tissue that have a natural pain-reducing effect. Warm liquids like tea or broth soothe in a different way, by promoting blood flow and keeping the tissue moist. Salt water gargles help draw excess fluid out of swollen tissue, which can reduce that tight, painful feeling when you swallow.
Warning Signs That Need Urgent Attention
Most sore throats are harmless and self-limiting, but a few specific symptoms signal something more dangerous. Epiglottitis, a swelling of the tissue flap that covers your airway, is a medical emergency. It can obstruct breathing rapidly and requires immediate treatment.
Call emergency services or go to an emergency room if you or someone you’re with develops any of these symptoms alongside a sore throat:
- Stridor: an unusual, high-pitched sound when breathing in
- Difficulty breathing or a feeling that the airway is closing
- Inability to swallow or severe pain with swallowing
- Drooling (because swallowing has become too difficult or painful)
- A muffled or “hot potato” voice
- Leaning forward or sitting upright to make breathing easier
In children, watch for unusual restlessness or anxiety combined with any of the above. Epiglottitis progresses quickly, and keeping the person calm and upright while waiting for help can make breathing easier.
Outside of emergencies, it’s worth getting checked if your sore throat lasts longer than ten days, comes with a fever above 101°F (38.3°C) that persists beyond a couple of days, or is accompanied by a rash, joint pain, or blood in your saliva.