A sore throat is most often caused by a viral infection, like the common cold or flu. But viruses aren’t the only explanation. Acid reflux, dry indoor air, post-nasal drip, and bacterial infections can all make your throat hurt, and each one feels slightly different and calls for a different response.
Viral Infections: The Most Common Cause
The vast majority of sore throats are caused by viruses. Cold and flu viruses inflame the tissue lining your throat, producing that raw, scratchy feeling that typically peaks in the first two or three days and resolves within a week. If your sore throat comes with a cough, runny nose, hoarseness, or pink eye, a virus is the most likely culprit. Antibiotics won’t help in this case because they only work against bacteria.
Mono is a viral infection worth knowing about separately. Caused by the Epstein-Barr virus, it produces an unusually severe sore throat alongside extreme fatigue, fever, headaches, body aches, and swollen lymph nodes in the neck and armpits. Most people recover in two to four weeks, but some feel fatigued for much longer. In rare cases, symptoms can linger for six months. A swollen liver or spleen can also develop, which is why doctors typically advise avoiding contact sports during recovery.
Strep Throat and Bacterial Infections
Group A Streptococcus bacteria cause strep throat, which can feel very similar to a viral sore throat. The key difference is what’s absent: strep throat usually does not come with a cough, runny nose, or hoarseness. Instead, it tends to hit fast with a high fever, painful swallowing, and sometimes white patches or red spots on the back of the throat. Swollen lymph nodes at the front of your neck are another common sign.
Strep matters because untreated cases can lead to complications affecting the heart and kidneys. A rapid strep test or throat culture at a clinic takes only minutes. If the test is positive, a course of antibiotics clears the infection and you’ll typically feel better within a day or two of starting treatment.
Acid Reflux That Reaches Your Throat
If your throat has been sore for weeks without any cold symptoms, acid reflux may be responsible. A condition called laryngopharyngeal reflux (LPR) occurs when stomach acid travels past the esophagus and reaches the throat. It only takes a small amount of acid, along with digestive enzymes like pepsin, to irritate the delicate tissue up there. Unlike your esophagus, your throat doesn’t have a protective lining or the ability to wash reflux away, so the acid lingers and does more damage.
The tricky part is that most people with LPR don’t feel the classic heartburn or chest burning you’d associate with reflux. Instead, you might notice a persistent sore throat, frequent throat clearing, a feeling of something stuck in your throat, or a hoarse voice. Many people assume they have allergies or a cold that won’t go away. It’s also common for LPR to first appear after a throat infection, because the initial irritation makes the tissue more vulnerable to acid damage going forward.
Eating smaller meals, avoiding food within three hours of lying down, and elevating the head of your bed can all reduce reflux episodes. If lifestyle changes don’t help, acid-reducing medications are the next step.
Post-Nasal Drip
Your nose and sinuses constantly produce mucus. Normally you swallow it without noticing. But when allergies, a sinus infection, or a cold ramp up mucus production, the excess drips down the back of your throat and irritates it. Your tonsils and surrounding tissue can swell in response, creating a sore, uncomfortable feeling that’s often worse in the morning after a night of mucus pooling while you slept.
Treating the underlying cause, whether that’s managing allergies with antihistamines or clearing a sinus infection, usually resolves the throat pain. Saline nasal rinses can also help by thinning the mucus and flushing it out before it reaches your throat.
Dry Air and Other Environmental Irritants
If your throat feels scratchy every morning but improves as the day goes on, dry indoor air is a likely suspect. Your throat relies on a thin layer of mucus to stay comfortable. When humidity drops too low, that mucus layer dries out, leaving your throat raw and inflamed. Indoor humidity should stay between 30% and 50%. In winter, heated air often falls well below that range.
A humidifier in your bedroom can make a noticeable difference. Breathing through your mouth while sleeping, which often happens with nasal congestion, compounds the problem by bypassing your nose’s natural ability to warm and moisten air. Cigarette smoke, chemical fumes, and heavy air pollution can also irritate the throat lining directly.
Easing the Pain at Home
Regardless of the cause, a few strategies help with throat pain. Over-the-counter pain relievers like ibuprofen and acetaminophen reduce both pain and inflammation. Stay under the daily maximum for acetaminophen, which is 4,000 milligrams in 24 hours, though most people do fine with less. Warm liquids, honey (for anyone over age one), and throat lozenges can also soothe irritation. Gargling with warm salt water, about half a teaspoon in a full glass of water, temporarily reduces swelling.
Staying hydrated is especially important. Fluids keep your throat’s mucus lining intact and help your body fight infection if one is present. Cold foods like ice pops can numb pain temporarily.
Signs That Need Prompt Attention
Most sore throats are harmless and clear up on their own, but a few warning signs call for immediate medical care. Difficulty breathing, inability to swallow, trouble opening your mouth, or unusual drooling (especially in children) are all red flags. These can signal a peritonsillar abscess, which is a pocket of infection near the tonsils, or swelling of the epiglottis, the small flap that covers your windpipe when you swallow. Either one can block the airway.
A sore throat lasting longer than a week, especially with a fever above 101°F, also warrants a visit. The same goes for recurring sore throats, blood in your saliva, a lump in your neck, or persistent hoarseness lasting more than two weeks. These don’t always mean something serious, but they’re worth investigating.