A sore throat is almost always caused by inflammation, and in most cases, a virus is to blame. Between 50% and 80% of sore throats come from viral infections like the common cold, flu, or COVID-19. Most clear up on their own within three to ten days without any specific treatment. But understanding what’s actually happening in your throat, what might be causing it, and which symptoms deserve attention can help you figure out your next steps.
Why a Sore Throat Actually Hurts
Your throat is lined with bare nerve endings that don’t have any protective covering. When a virus or bacterium infects the tissue, your immune system responds by releasing inflammatory chemicals, primarily prostaglandins and bradykinin. These chemicals serve a purpose: they increase blood flow to the area and recruit immune cells to fight the infection. But they also act directly on those exposed nerve endings, triggering pain signals.
Bradykinin is especially potent. It stimulates pain fibers, causes blood vessels to widen, and makes capillary walls more permeable, which leads to the swelling you feel when you try to swallow. It also sensitizes your throat’s temperature receptors so that they fire at normal body temperature instead of only at high heat. That’s why an inflamed throat can feel like it’s burning even when nothing hot has touched it. Prostaglandins amplify this effect, lowering the threshold at which those same pain receptors activate.
This is also why cold things like ice chips or cool liquids tend to feel soothing. Your throat has separate receptors that respond to cool temperatures, and activating them produces a mild analgesic effect that temporarily counteracts the pain signals from inflammation.
The Most Common Causes
Viruses cause the vast majority of sore throats. The usual suspects are rhinoviruses (the common cold), influenza, COVID-19, and mononucleosis. These infections typically come with other symptoms like a runny nose, cough, mild fever, or body aches. The throat pain is part of a package, and it resolves as the infection runs its course.
Bacterial infections are less common but more consequential. Group A Streptococcus, the bacterium behind strep throat, accounts for 5% to 15% of sore throats in adults and 20% to 30% in children. Strep tends to come on suddenly, often with a high fever, swollen lymph nodes in the neck, and sometimes white patches on the tonsils. It typically does not come with a cough or runny nose, which is one way to distinguish it from a viral infection.
Non-infectious causes are worth considering too, especially if your throat pain keeps coming back or never fully goes away:
- Allergies: Reactions to pollen, dust, mold, or pet dander can inflame the throat, particularly when postnasal drip irritates the tissue.
- Dry air: Indoor heating in winter dries out the mucous membranes. Breathing through your mouth while sleeping makes this worse.
- Irritants: Tobacco smoke, alcohol, air pollution, and spicy foods can all cause ongoing throat soreness.
- Silent reflux: Stomach acid can travel past the esophagus and reach the throat, a condition called laryngopharyngeal reflux. Because it often doesn’t cause the typical heartburn associated with acid reflux, it’s sometimes called “silent reflux.” The throat tissues lack the protective lining that the esophagus has, so even small amounts of acid and digestive enzymes can cause persistent irritation, hoarseness, and a feeling of something stuck in your throat.
How Long It Typically Lasts
Most viral sore throats follow a predictable arc. Pain usually peaks around days two or three, then gradually improves. The full timeline from start to finish is three to ten days, with most people feeling significantly better within a week. If you also have cold symptoms like congestion, those may linger a few days longer than the throat pain itself.
Strep throat, once treated with antibiotics, typically starts improving within one to two days. Without treatment, it can last longer and carries the risk of complications like rheumatic fever or kidney inflammation, which is why getting tested matters when the symptoms fit.
A sore throat that persists beyond two weeks, especially without other signs of infection, points toward a non-infectious cause. That’s when allergies, reflux, or environmental irritants become the more likely explanation.
Viral vs. Strep: How to Tell
You can’t diagnose strep throat just by looking, but the pattern of symptoms offers strong clues. A sore throat with a cough, runny nose, and hoarseness is almost certainly viral. A sore throat with sudden onset, fever over 101°F, swollen tender lymph nodes, and no cough is much more likely to be strep.
The standard way to confirm strep is a rapid antigen test, the quick swab you can get at a clinic or pharmacy. These tests have a sensitivity of about 86%, meaning they correctly identify strep in roughly 86 out of 100 people who actually have it. Specificity is higher, around 95%, so a positive result is reliable. If the rapid test is negative but strep is still strongly suspected (especially in children), a throat culture can catch the cases the rapid test misses.
What Helps at Home
For a standard viral sore throat, the goal is comfort while your immune system does its work. Over-the-counter pain relievers like ibuprofen or acetaminophen are the most effective options. They reduce both pain and inflammation. Adults can take 650 to 1,000 milligrams of acetaminophen every four to six hours as needed. Ibuprofen has the added benefit of directly targeting the prostaglandins driving the inflammation in your throat.
Gargling with salt water is one of the oldest home remedies, and it has some evidence behind it. A clinical trial comparing saltwater gargling to an antiseptic solution in 100 patients with non-bacterial sore throats found that the salt solution significantly reduced pain, difficulty swallowing, and throat swelling. A simple mixture of about half a teaspoon of salt in a glass of warm water, gargled for 15 to 30 seconds, can be repeated several times a day.
Other measures that help: staying hydrated (warm liquids like tea or broth are especially soothing), using a humidifier if your indoor air is dry, and sucking on ice chips or popsicles to activate those cooling receptors in the throat that naturally dampen pain signals. Avoid cigarette smoke and alcohol, both of which directly irritate inflamed tissue.
Symptoms That Need Attention
Most sore throats are harmless inconveniences, but a few patterns warrant prompt medical evaluation. Difficulty breathing or a feeling that your airway is narrowing is the most urgent. Inability to swallow your own saliva (drooling in an adult or older child) can signal a peritonsillar abscess or severe swelling that needs immediate care. A muffled, “hot potato” voice alongside throat pain also suggests significant swelling near the airway.
Other reasons to get checked: a sore throat lasting longer than a week without improvement, fever above 101°F that persists beyond a couple of days, a visible lump or asymmetric swelling in the throat, blood in your saliva, or recurring sore throats (six or more per year). Joint pain developing after a sore throat is rare but important, as it can be an early sign of rheumatic fever following untreated strep.
For sore throats that keep returning without a clear infectious cause, it’s worth considering silent reflux, chronic allergies, or environmental exposures. These causes are easy to overlook because they don’t come with the fever and fatigue of an infection, but they respond well to targeted treatment once identified.