Sore Throat: Causes, Symptoms & When to See a Doctor

What Is a Sore Throat?

A sore throat (pharyngitis) is pain, scratchiness, or irritation in the throat that often worsens when swallowing. It is usually caused by viral infections like the common cold, though bacterial infections, environmental factors, and other conditions can also be responsible. Most sore throats resolve without treatment within 5-7 days.

A sore throat is one of the most common medical complaints, particularly during the colder months when respiratory infections are more prevalent. The condition occurs when the tissues of the pharynx (the back of the throat) become inflamed, leading to discomfort that can range from mild irritation to severe pain that interferes with eating, drinking, and speaking. Understanding what causes a sore throat is the first step in determining the appropriate treatment approach.

The pharynx is a tube-like structure that connects the nasal passages and mouth to the esophagus and larynx (voice box). When infectious agents, irritants, or other factors cause inflammation in this area, the result is the characteristic pain and discomfort we recognize as a sore throat. The severity of symptoms can vary significantly depending on the underlying cause, with some conditions causing mild discomfort that barely affects daily activities while others can make swallowing liquids extremely painful.

Most sore throats are self-limiting, meaning they will resolve on their own without specific medical treatment. However, certain types of sore throat, particularly those caused by bacterial infections, may require antibiotic treatment to prevent complications. This is why understanding the different types of sore throat and their characteristics is important for proper management.

Anatomy of the Throat

The throat contains several important structures that can become affected when you have pharyngitis. The tonsils, two oval-shaped pads of tissue at the back of the throat, are part of the immune system and often become enlarged and inflamed during infections. The adenoids, located higher in the throat behind the nose, can also become involved, particularly in children. When a doctor examines your throat, they are looking for signs of inflammation, swelling, and any visible changes that might indicate the type and severity of your infection.

The lymph nodes in the neck, often called "glands," frequently become swollen and tender when the throat is infected. This is because they are working to filter out and fight the infectious agents. Swollen lymph nodes, particularly in the front of the neck just below the jaw, are a common finding during a throat infection and can persist for several days even after other symptoms have improved.

What Causes a Sore Throat?

Sore throats are most commonly caused by viral infections (70-95% of cases), including the common cold, influenza, and COVID-19. Bacterial infections like strep throat account for 5-36% of cases, while non-infectious causes include allergies, dry air, acid reflux, voice strain, and environmental irritants.

Understanding the cause of your sore throat is crucial because it determines whether you need medical treatment, what kind of treatment will be effective, and how long you can expect symptoms to last. The causes of sore throat can be broadly divided into infectious and non-infectious categories, with infectious causes being far more common.

Viral Infections (Most Common)

Viral infections account for the vast majority of sore throats, with estimates ranging from 70% to 95% of all cases. These infections typically cause symptoms that extend beyond the throat, including runny nose, cough, sneezing, and mild body aches. The most common viral causes include rhinoviruses (which cause the common cold), influenza viruses, coronaviruses (including COVID-19), respiratory syncytial virus (RSV), and Epstein-Barr virus (which causes mononucleosis or "mono").

When a virus causes a sore throat, the immune system responds by sending white blood cells to the affected area, causing inflammation and swelling. This inflammatory response is what produces the pain and discomfort you feel. Antibiotics are completely ineffective against viral infections, which is why doctors do not prescribe them for viral sore throats. Taking antibiotics when they are not needed contributes to antibiotic resistance, a growing public health concern.

The common cold is the most frequent cause of sore throat, affecting adults 2-3 times per year on average and children even more frequently. Cold symptoms typically include nasal congestion, sneezing, mild cough, and low-grade fever in addition to throat discomfort. The sore throat associated with a cold usually develops gradually and is often accompanied by a scratchy or tickling sensation.

Bacterial Infections

While less common than viral infections, bacterial sore throats are important to identify because they may require antibiotic treatment to prevent complications. Streptococcus pyogenes (group A streptococcus) is the most common bacterial cause, responsible for what is commonly called "strep throat." Strep throat is most common in children aged 5-15 years but can occur at any age.

Strep throat typically causes more severe symptoms than viral infections and characteristically does NOT include the runny nose and cough associated with colds. Classic symptoms include sudden onset of severe sore throat, high fever, red and swollen tonsils (often with white patches or pus), swollen and tender lymph nodes in the neck, and sometimes a sandpaper-like rash (scarlet fever). However, these symptoms can overlap with viral infections, which is why laboratory testing is often necessary to confirm the diagnosis.

Other bacterial causes of sore throat include Mycoplasma pneumoniae, Chlamydia pneumoniae, and Neisseria gonorrhoeae (in cases of sexually transmitted infection). While these are less common, they may be considered in certain clinical situations.

Non-Infectious Causes

Not all sore throats are caused by infections. Several environmental and lifestyle factors can irritate the throat and cause discomfort. Allergies can cause postnasal drip, where mucus drips from the back of the nose down the throat, causing irritation and a sore, scratchy feeling. This is particularly common during allergy season or when exposed to indoor allergens like dust mites or pet dander.

Dry air, especially during winter when indoor heating reduces humidity, can dry out the throat and cause irritation. Using a humidifier, particularly at night, can help alleviate this type of sore throat. Similarly, breathing through the mouth (due to nasal congestion or during sleep) can dry out the throat and cause morning soreness.

Gastroesophageal reflux disease (GERD), where stomach acid flows back into the esophagus, can cause a burning sensation in the throat, particularly in the morning or after eating. This is sometimes called laryngopharyngeal reflux (LPR) when it specifically affects the throat. Unlike typical heartburn, LPR may not cause the classic burning sensation in the chest, making it harder to recognize.

Voice strain from yelling, singing, or prolonged talking can inflame the vocal cords and cause throat discomfort and hoarseness. This is particularly common among teachers, singers, and others who use their voices professionally. Environmental irritants such as cigarette smoke (including secondhand smoke), air pollution, and chemical fumes can also irritate the throat.

What Are the Symptoms of a Sore Throat?

Sore throat symptoms include throat pain or scratchiness, difficulty swallowing, red or swollen tonsils, swollen lymph nodes, hoarseness, and fever. Viral sore throats typically include runny nose and cough, while bacterial infections (strep throat) often cause severe pain without cold symptoms and may have white patches on the tonsils.

The symptoms of a sore throat can vary significantly depending on the underlying cause. Recognizing the pattern of your symptoms can help determine whether you're dealing with a viral infection that will resolve on its own or a bacterial infection that may benefit from antibiotic treatment. However, because symptoms often overlap, laboratory testing is frequently necessary for an accurate diagnosis.

The primary symptom is, of course, pain or discomfort in the throat. This can range from a mild scratchy sensation to severe pain that makes swallowing difficult. The pain may be constant or may come and go, and it often worsens when swallowing. Many people describe it as a burning, raw, or scratchy feeling. In some cases, the pain may radiate to the ears, particularly when swallowing.

Symptoms Suggesting Viral Infection

When a sore throat is caused by a viral infection, it is usually accompanied by other cold symptoms. These include nasal congestion or runny nose, sneezing, cough (often starting a day or two after the sore throat begins), mild body aches, low-grade fever (typically below 101°F/38.3°C), and general malaise or feeling unwell. The onset is usually gradual, with symptoms developing over 1-2 days.

The sore throat associated with a cold often feels scratchy or tickly rather than severely painful. Swallowing may be uncomfortable but is usually manageable. The tonsils may appear red and slightly swollen but typically do not have the dramatic swelling or white patches seen in bacterial infections. Symptoms usually peak around day 2-3 and then gradually improve over the following 4-5 days.

Symptoms Suggesting Strep Throat

Strep throat (streptococcal pharyngitis) has a somewhat different symptom pattern that can help distinguish it from viral infections, though considerable overlap exists. Classic strep throat symptoms include sudden onset of severe sore throat (often described as the worst sore throat ever experienced), high fever (often above 101°F/38.3°C), severely red and swollen tonsils, white patches or streaks of pus on the tonsils, small red spots on the roof of the mouth (palate), swollen and very tender lymph nodes in the front of the neck, and headache.

Importantly, strep throat typically does NOT cause cough, runny nose, or the typical cold symptoms. This absence of cough and nasal symptoms is a helpful distinguishing feature, though it is not definitive. Some children with strep throat may also develop nausea, vomiting, or abdominal pain, which can sometimes lead to initial misdiagnosis.

A rash resembling sunburn with small bumps (sandpaper texture) may develop, particularly in children. This is called scarlet fever and indicates a streptococcal infection that is producing certain toxins. While the name sounds alarming, scarlet fever is treated the same way as strep throat and is not more dangerous when properly treated.

Warning Signs Requiring Immediate Attention

While most sore throats are not serious, certain symptoms indicate potentially dangerous conditions that require immediate medical evaluation. You should seek emergency care if you experience difficulty breathing or feeling that your airway is closing, inability to swallow saliva (drooling), severe pain on one side of the throat with difficulty opening your mouth (possible peritonsillar abscess), muffled or "hot potato" voice, neck stiffness with high fever, or signs of dehydration from inability to drink fluids.

When Should You See a Doctor for a Sore Throat?

See a doctor if your sore throat lasts more than a week, you have difficulty breathing or swallowing, you cannot swallow saliva, you have severe pain on one side of the throat, you have fever for several days without cold symptoms, or you have recurring episodes. Children and immunocompromised individuals should seek care earlier.

Most sore throats resolve on their own within a week without the need for medical intervention. However, knowing when to seek professional evaluation is important for identifying conditions that may require specific treatment or that could lead to complications if left untreated. The decision to see a doctor depends on the severity of symptoms, their duration, and certain risk factors.

Healthcare providers have developed clinical scoring systems to help determine the likelihood of strep throat and guide testing decisions. The most commonly used is the Centor criteria (modified McIsaac), which assigns points for fever over 100.4°F (38°C), absence of cough, tender anterior cervical lymph nodes, tonsillar swelling or exudates, and age (with adjustments for children and older adults). However, these scores are only moderately accurate and are best used alongside clinical judgment and testing.

Situations Requiring Medical Evaluation

You should contact your healthcare provider if you have a sore throat lasting more than one week without improvement, difficulty breathing or shortness of breath (seek emergency care), inability to swallow liquids adequately leading to dehydration risk, severe pain on one side of the throat that worsens, significant difficulty opening your mouth, fever over 101°F (38.3°C) lasting more than a few days, blood in saliva or phlegm, joint pain or swelling accompanying the sore throat, a rash that develops during the illness, or recurring sore throats (several episodes in a year).

Parents should be particularly vigilant with children, as they may not be able to clearly communicate their symptoms. Seek evaluation for a child who is drooling excessively or having difficulty swallowing, refusing to drink fluids, has a very high fever, appears unusually sick or lethargic, has difficulty breathing, or has severe symptoms that are worsening rather than improving.

Individuals with weakened immune systems (due to conditions like HIV/AIDS, cancer treatment, or immunosuppressive medications) should have a lower threshold for seeking medical evaluation, as they may be more susceptible to serious infections and complications.

How Is a Sore Throat Diagnosed?

Diagnosis involves physical examination of the throat, lymph nodes, and ears. If strep throat is suspected, a rapid strep test provides results in 10-15 minutes, while a throat culture takes 24-48 hours but is more accurate. Testing is important because clinical examination alone cannot reliably distinguish viral from bacterial causes.

When you visit a healthcare provider for a sore throat, they will take a medical history and perform a physical examination. This typically includes questions about your symptoms, their duration, and any associated symptoms or recent exposures. The physical examination focuses on the throat, tonsils, lymph nodes, and ears, but may also include listening to your lungs and checking for rashes.

Physical Examination

During the examination, the doctor will look at your throat using a light and tongue depressor. They are looking for redness, swelling, and any visible pus or white patches on the tonsils. The degree of tonsillar enlargement is noted, as is the appearance of the pharynx and soft palate. Small red spots (petechiae) on the palate are more common in strep throat but can occur with other conditions as well.

The doctor will also feel the lymph nodes in your neck. Tender, swollen lymph nodes in the front of the neck (anterior cervical nodes) are common with sore throats and are particularly prominent in strep throat. The ears are often examined as well, since ear infections can occur alongside throat infections, and throat pain can sometimes radiate to the ears.

Laboratory Tests

Because clinical examination alone cannot reliably distinguish strep throat from viral infections, laboratory testing is often performed when strep is suspected. The rapid antigen detection test (RADT), commonly called a "rapid strep test," provides results in 10-15 minutes. A swab is taken from the back of the throat and tonsils, and the test detects proteins specific to group A streptococcus.

The rapid strep test has high specificity (meaning a positive result reliably indicates strep) but somewhat lower sensitivity (meaning it can miss some cases). If the rapid test is positive, strep throat is confirmed and antibiotic treatment can be started. If the rapid test is negative, a throat culture may be performed, particularly in children and adolescents, to catch cases that the rapid test might have missed.

A throat culture involves sending the swab to a laboratory where bacteria are grown over 24-48 hours. This is more accurate than the rapid test but takes longer to get results. In adults, a negative rapid test is often considered sufficient to rule out strep throat because the risk of complications like rheumatic fever is very low. In children, many providers will perform a culture when the rapid test is negative.

How Is a Sore Throat Treated?

Viral sore throats are treated with supportive care: rest, fluids, pain relievers (paracetamol or ibuprofen), and home remedies like warm salt water gargles. Bacterial sore throat (strep) requires antibiotics, typically penicillin or amoxicillin for 10 days. Antibiotics are ineffective and inappropriate for viral infections.

Treatment for sore throat depends entirely on the underlying cause. The fundamental principle is that viral infections require only supportive care while bacterial infections may benefit from antibiotic treatment. Taking antibiotics for a viral infection provides no benefit, exposes you to potential side effects, and contributes to antibiotic resistance.

Supportive Care for All Sore Throats

Regardless of the cause, several measures can help relieve sore throat symptoms. Staying well-hydrated is essential, as fluids help keep the throat moist and prevent dehydration, especially if fever is present. Warm liquids like tea, broth, or warm water with honey can be particularly soothing. Cool liquids and ice pops can also help numb the throat temporarily.

Over-the-counter pain relievers such as paracetamol (acetaminophen) or ibuprofen can effectively reduce throat pain and fever. These medications are safe for most adults when used as directed and can significantly improve comfort. Aspirin should not be given to children or teenagers due to the risk of Reye's syndrome.

Throat lozenges and sprays can provide temporary relief by keeping the throat moist and, in some cases, providing mild numbing. While they don't treat the underlying cause, they can make symptoms more manageable. Sugar-free options are better for dental health if you're using them frequently.

Gargling with warm salt water (about half a teaspoon of salt in a full glass of warm water) is a time-tested remedy that can help reduce throat swelling and loosen mucus. This can be done several times a day. While not a cure, many people find it provides temporary relief.

Rest is important, particularly if you have a fever or feel generally unwell. This doesn't necessarily mean bed rest, but you should avoid strenuous activities and give your body the energy it needs to fight the infection. Resting your voice can also help if you have hoarseness or voice strain.

Antibiotic Treatment for Strep Throat

When strep throat is confirmed through testing, antibiotic treatment is recommended. The primary goals of antibiotic treatment are to prevent complications (particularly rheumatic fever), reduce the duration and severity of symptoms, reduce transmission to others, and prevent suppurative complications like peritonsillar abscess.

Penicillin V or amoxicillin are the first-line treatments for strep throat and are typically given for 10 days. These antibiotics are highly effective against group A streptococcus and are well-tolerated. For patients with penicillin allergy, alternatives include cephalexin (if the allergy is not severe), azithromycin, or clindamycin.

Most people begin to feel better within 24-48 hours of starting antibiotics. However, it is crucial to complete the entire course of antibiotics as prescribed, even if you feel better before finishing. Stopping antibiotics early can lead to recurrence of infection and potentially contribute to antibiotic resistance.

Patients with strep throat are considered contagious until they have been on antibiotics for at least 24 hours. After this point, they can typically return to school or work if they feel well enough. Without antibiotics, a person with strep throat may remain contagious for 2-3 weeks.

When Antibiotics Are NOT Needed

It bears repeating that antibiotics are completely ineffective against viral infections, which cause the majority of sore throats. Taking antibiotics when they are not needed exposes you to potential side effects (including allergic reactions, diarrhea, and yeast infections) without any benefit. Furthermore, unnecessary antibiotic use contributes to the growing problem of antibiotic-resistant bacteria.

If you have a sore throat with typical cold symptoms (runny nose, cough, sneezing), it is almost certainly viral and will not benefit from antibiotics. Even if you have mononucleosis (which can cause severe sore throat and swollen tonsils), antibiotics are not helpful because it is caused by a virus.

What Can You Do at Home to Relieve a Sore Throat?

Effective home remedies include drinking warm liquids (tea with honey), gargling with warm salt water, using throat lozenges, running a humidifier, resting your voice, and taking over-the-counter pain relievers. Avoid irritants like cigarette smoke and very dry air. Most viral sore throats improve significantly within 3-5 days with these measures.

For the majority of sore throats, home care is all that is needed. These self-care measures focus on relieving symptoms and supporting your body's natural healing process. Many of these remedies have been used for generations and, while they may not cure the underlying cause, they can significantly improve comfort during recovery.

Hydration and Warm Liquids

Staying well-hydrated is one of the most important aspects of sore throat care. Fluids help keep the throat moist, thin mucus secretions, and prevent dehydration, which can worsen feelings of illness. Aim to drink plenty of water throughout the day. If you have a fever, your fluid needs are even higher.

Warm liquids are particularly soothing for a sore throat. Options include warm water with honey and lemon, herbal teas (especially those with anti-inflammatory properties like chamomile), warm broth or soup, and warm water with honey alone. The warmth helps increase blood flow to the throat, while honey coats and soothes the irritated tissues.

Some people find cool liquids helpful as well, as they can help numb the throat temporarily. Ice pops, smoothies, and cold water are all reasonable options. Experiment to see what feels best for you.

Salt Water Gargle

Gargling with warm salt water is a simple, inexpensive remedy that many people find helpful. The salt helps reduce swelling and can loosen mucus. To prepare, dissolve about half a teaspoon of salt in a full glass (8 ounces/240 ml) of warm water. Gargle for about 30 seconds, then spit out the solution. This can be repeated several times throughout the day.

Children who can gargle safely can also use this remedy, though you should supervise to ensure they don't swallow the salt water. For children who cannot gargle, other methods of soothing the throat should be used instead.

Environmental Modifications

Dry air can worsen sore throat symptoms, particularly during winter when indoor heating reduces humidity. Using a humidifier in your bedroom can help keep the air moist and reduce throat irritation. Clean your humidifier regularly to prevent mold growth.

Avoiding irritants is also important. Cigarette smoke (including secondhand smoke) is particularly harmful to an already irritated throat. Strong fumes from cleaning products, paint, or other chemicals should also be avoided when possible.

Rest and Voice Care

Getting adequate rest allows your body to direct energy toward fighting the infection. While you may not need to stay in bed, avoid strenuous activities and prioritize sleep. If you have a fever, rest is particularly important.

If you have hoarseness or voice strain along with your sore throat, resting your voice is important. Avoid shouting, whispering (which actually strains the voice more than speaking softly), and prolonged talking. If your job requires heavy voice use, consider taking time off if possible.

How Can You Prevent a Sore Throat?

Prevent sore throat by washing hands frequently, avoiding close contact with sick individuals, not sharing drinks or utensils, keeping hands away from your face, maintaining good general health, using a humidifier in dry environments, and avoiding known irritants like cigarette smoke.

While it's impossible to prevent all sore throats, certain measures can significantly reduce your risk of developing respiratory infections. These preventive strategies are particularly important during cold and flu season and in situations where you might be exposed to infectious individuals.

Hand Hygiene

Proper hand hygiene is the single most effective way to prevent respiratory infections. Viruses and bacteria that cause sore throats are often transmitted through contact with contaminated surfaces or direct contact with infected individuals. Wash your hands frequently with soap and water for at least 20 seconds, especially after using the bathroom, before eating, after touching common surfaces in public, and after coughing, sneezing, or blowing your nose.

When soap and water are not available, alcohol-based hand sanitizers (containing at least 60% alcohol) are an effective alternative. Keep hand sanitizer accessible in your bag, car, or at your desk.

Avoiding Transmission

Respiratory infections spread through droplets when an infected person coughs, sneezes, or talks. Maintaining distance from people who are visibly ill can reduce your risk. Similarly, if you are sick, staying home helps prevent spreading the infection to others.

Avoid sharing drinking glasses, utensils, water bottles, and other personal items with others, even family members. This is particularly important during active illness but is a good practice in general. Additionally, avoid touching your face, particularly your nose, mouth, and eyes, as this is how many respiratory viruses enter the body.

Maintaining General Health

A healthy immune system is better equipped to fight off infections. Getting adequate sleep (7-9 hours for most adults), eating a balanced diet rich in fruits and vegetables, exercising regularly, and managing stress all contribute to immune function. While these measures won't guarantee you won't get sick, they give your body the best chance of fighting off infections quickly.

What Are the Complications of Sore Throat?

Most sore throats resolve without complications. However, untreated strep throat can rarely lead to rheumatic fever (affecting the heart) or kidney problems. More immediate complications include peritonsillar abscess (collection of pus near the tonsil), which causes severe one-sided pain and difficulty opening the mouth. Recurring strep throat may require tonsillectomy.

While the vast majority of sore throats resolve without any lasting effects, certain complications can occur, particularly when bacterial infections go untreated. Understanding these potential complications helps explain why proper diagnosis and treatment of strep throat is important, and helps you recognize warning signs that require immediate medical attention.

Complications of Strep Throat

Untreated strep throat can, in rare cases, lead to serious complications. Rheumatic fever is an inflammatory condition that can affect the heart, joints, nervous system, and skin. It typically occurs 2-4 weeks after an untreated strep infection. While rare in developed countries with access to antibiotics, rheumatic fever remains a concern and is a primary reason for treating confirmed strep throat with antibiotics. Rheumatic fever can cause permanent heart valve damage (rheumatic heart disease).

Post-streptococcal glomerulonephritis is kidney inflammation that can occur after strep infection. It typically causes dark urine, swelling, and high blood pressure. Unlike rheumatic fever, antibiotic treatment may not prevent this complication, but most cases resolve without lasting kidney damage.

Local Complications

Peritonsillar abscess (quinsy) is a collection of pus that forms next to the tonsil, usually as a complication of tonsillitis. Symptoms include severe sore throat (usually worse on one side), difficulty opening the mouth (trismus), muffled or "hot potato" voice, drooling, and fever. This is a medical emergency requiring drainage of the abscess and antibiotic treatment.

Retropharyngeal abscess is an infection in the space behind the throat that is more common in children. It can cause severe throat pain, difficulty swallowing, neck stiffness, and fever. This also requires urgent medical attention.

Chronic or Recurring Issues

Some individuals experience recurring strep throat infections. When someone has multiple strep throat infections in a year (generally defined as 7 or more episodes in one year, 5 or more per year for two consecutive years, or 3 or more per year for three consecutive years), tonsillectomy (surgical removal of the tonsils) may be considered. Tonsillectomy has been shown to reduce the frequency of throat infections in these cases.

Children who have frequent tonsillitis or very large tonsils causing breathing problems during sleep may also be candidates for tonsillectomy. This decision is made on an individual basis considering the frequency and severity of infections and their impact on quality of life.