Sore throat: common causes

A sore throat is a sensation of dryness, scratchiness, tickling, a "lump," or a constant need to clear the throat. It is not a distinct disorder in itself. It is a symptom that can occur with both short-term irritation of the mucous membrane and chronic diseases of the nose, pharynx, larynx, esophagus, and respiratory tract. Therefore, the correct question is not "how to treat a sore throat," but "what exactly is causing it?" [1]

In clinical practice, it's important to distinguish between a sore throat and a scratchy throat. Acute pain when swallowing, high fever, and plaque on the tonsils often suggest pharyngitis or tonsillitis. However, a persistent tickling sensation, a dry, uncomfortable cough, a need to clear the throat, and hoarseness without overt fever are much more likely to indicate postnasal drip, allergic rhinitis, mouth breathing, dry mucous membranes, chronic cough syndrome, or reflux-associated symptoms. [2]

In many people, the symptom begins after a common viral upper respiratory tract infection. The UK's National Institute for Health and Clinical Excellence notes that acute sore throat is often viral in origin and typically resolves in about a week without antibiotics. However, if a dry cough, throat clearing, and irritation persist after the infection, it's important to evaluate not only the virus but also any remaining mucosal hypersensitivity, mucus drainage, nasal obstruction, and other causes. [3]

A particular complication is that the sore throat is often part of a broader syndrome. In some patients, it is accompanied by a cough, in others by hoarseness, and in others by a sensation of mucus in the throat or a foreign body sensation. Therefore, the same complaint can lead to various diagnostic directions: from allergies and rhinosinusitis to laryngeal hypersensitivity and oncologically concerning conditions. [4]

For a new, modern article, it's especially important to explain to patients a simple fact: a sore throat isn't always associated with an infection and doesn't always require antibiotics. In many cases, the key to treatment lies not in "antimicrobial therapy," but in eliminating the trigger: restoring nasal breathing, treating allergies, correcting reflux symptoms, changing medications, or reducing the load on the larynx. [5]

Table 1. What is most often hidden behind a sore throat?

The most likely reason	What does the diagnosis usually suggest?
Viral irritation of the mucous membrane	Short-term course, runny nose, cough, gradual improvement within 1 week
Postnasal drip	Feeling of mucus in the back of the throat, frequent throat clearing, coughing, nasal congestion
Allergic rhinitis	Sneezing, itchy nose, watery discharge, itchy roof of mouth, seasonality or contact with an allergen
Mouth breathing and dry mouth	Nighttime dryness, nasal congestion, dry feeling in the morning
Laryngopharyngeal symptoms and reflux	Hoarseness, lump in the throat, coughing, connection with food or heartburn is not expressed in everyone
Medicinal cause	Dry, irritating cough and "tickling" after starting an angiotensin-converting enzyme inhibitor
Laryngeal hypersensitivity	Increased sensitivity to odors, cold air, conversation, stress, and a feeling of constant irritation

Table based on: NICE, US Centers for Disease Control and Prevention, UK National Health Service, British Thoracic Society, US National Kidney Foundation. [6]

The main causes of a sore throat

The most common cause of persistent sore throat is postnasal drip, or mucus dripping down the back of the throat. The Centers for Disease Control and Prevention (CDC) lists postnasal drip, sore throat, and cough as typical symptoms of sinusitis, and current research on chronic cough shows that upper respiratory symptoms remain one of the most common contributors to persistent complaints. Patients typically describe it as "like something is running down the throat" or "like I have to constantly clear my throat." [7]

Allergic causes are very closely related to this group. In allergic rhinitis, inflammation begins in the nose, but symptoms often extend beyond it. The UK National Health Service (NHS) notes that sneezing, nasal itching, runny or stuffy nose, cough, and itchy palate are typical of allergic rhinitis. A 2024 review further emphasizes that when examining the back of the throat, a physician may see signs of postnasal drip. Therefore, a complaint of a "scratchy throat" is often a symptom of an untreated allergy. [8]

Another common cause is dry mucous membranes. Dry mouth and throat are aggravated by dehydration, medications, anxiety, mouth breathing, and persistent nasal congestion. The UK National Health Service specifically states that dry mouth is often associated with mouth breathing at night. In practice, this is especially noticeable in people with a deviated septum, chronic congestion, snoring, and the habit of sleeping with their mouth open. [9]

Reflux can indeed be a cause of throat irritation, but this category should not be oversimplified. The 2024 European Consensus on Laryngopharyngeal Reflux emphasizes that diagnosis requires a more precise approach, with multi-level impedance-pH monitoring considered the gold standard. The British Thoracic Society, meanwhile, notes that in most patients with chronic cough and upper respiratory symptoms, acid suppression alone is of limited benefit, and that patients with typical heartburn symptoms are most likely to respond. This means that a sore throat alone should not automatically lead to a diagnosis of reflux. [10]

Medicinal and neurosensory causes should be considered separately. Angiotensin-converting enzyme inhibitors can cause a persistent dry cough and a characteristic tickling, scratchy sensation in the throat. The US National Kidney Foundation describes this side effect as a dry, tic-like or scratchy discomfort in the throat, and the British Thoracic Society recommends discontinuing this medication in patients with chronic cough. Additionally, some people develop laryngeal hypersensitivity, when the larynx begins to overreact to odors, cold air, talking, laughter, and even normal bodily sensations. [11]

Table 2. How to guess the most likely cause based on complaints

Complaint or combination of symptoms	What is more likely?
Mucus down the back of the throat, constant coughing, nasal congestion	Postnasal drip, rhinosinusitis
Sneezing, itchy nose, itchy palate, runny nose	Allergic rhinitis
Dryness in the morning, snoring, sleeping with an open mouth	Mouth breathing, dry mucous membranes
Hoarseness, lump in the throat, worse after eating, but sometimes without heartburn	Laryngopharyngeal symptoms, possible reflux
Persistent dry cough after starting an antihypertensive drug	Angiotensin-converting enzyme inhibitor side effect
Reaction to perfume, cold air, conversation, stress	Laryngeal hypersensitivity
A brief episode against the background of a runny nose and a cold	Viral irritation of the mucous membrane

Table based on: NHS, CDC, British Thoracic Society, National Kidney Foundation, European Consensus on Laryngopharyngeal Reflux. [12]

When a sore throat is dangerous

Most cases of sore throat are not considered emergencies, but there are symptoms that necessitate home observation. Red flags include difficulty breathing, stridor, drooling, trismus, "hot potato" speech, severe unilateral pain, and increasing swelling of the neck. These signs require the exclusion of severe pharyngeal inflammation, peritonsillar inflammation, epiglottitis, and deep neck infections. [13]

A particularly dangerous situation is when the severity of complaints doesn't correspond to the modest findings on a routine examination of the oropharynx. For the clinician, this is an important clue to search for a deeper cause. Pediatric guidelines specifically list toxic appearance, respiratory distress, stridor, trismus, salivation, forced head position, and neck rigidity. The logic is the same in adults: the more symptoms impairing the airway, the less room for delay. [14]

A separate section is oncological alertness. Referral guidelines in the National Health Service of Scotland indicate that persistent unilateral sore throat or pain when swallowing for more than 3 weeks is a red flag and one of the best predictors of head and neck cancer after cervical nodules. Referred pain to the ear on the same side, progressive symptoms, hoarseness, and cervical swelling are also significant. [15]

Unintentional weight loss, hemoptysis, increasing hoarseness, difficulty swallowing, and a persistent unilateral foreign body sensation are also considered warning signs. These symptoms don't automatically indicate swelling, but they do indicate that the sore throat can no longer be dismissed as harmless "irritable pharynx." At this point, a full examination by an otolaryngologist is needed, not a symptomatic spray. [16]

The rule of thumb is simple: if the sore throat persists for weeks, becomes unilateral, is accompanied by pain, changes the voice, interferes with swallowing, or is accompanied by a cervical nodule, self-medication is no longer an option. The longer the symptom persists without a clear benign cause, the more important it is to have an instrumental examination of the larynx and pharynx. [17]

Table 3. Red flags for a sore throat

Symptom	Why is this dangerous?	Tactics
Stridor, increasing dyspnea	Threat to the respiratory tract	Immediate emergency care
Drooling, inability to swallow saliva	Possible severe inflammation of the epiglottis or a deep process	Urgent in-person assessment
Trismus, the "hot potato" speech	Possible peritonsillar process	Urgent direction
One-sided pain or pain when swallowing for more than 3 weeks	Oncological alertness	Urgent examination by an otolaryngologist
Hoarseness, cervical node, referred pain to the ear	Head and neck tumors are possible	Accelerated diagnostics
Rapid deterioration of general condition, swelling of the neck	A deep neck infection is possible.	Urgent assessment

Table based on: Royal Children's Hospital paediatric guidelines, Scottish referral guidelines for suspected head and neck cancer.[18]

Diagnostics: What exactly needs to be determined

The first stage of diagnosis is a detailed interview. The physician is concerned not only with the duration of the symptom but also with its rhythm: whether it is worse in the morning or evening, whether it is associated with food, whether it worsens after talking, in cold air, in a dusty room, during pollen season, at night, or after sleep. This alone allows one to roughly differentiate between infectious, nasal, reflux, and laryngeal hypersensitivity. [19]

The second step is to evaluate nasal symptoms. If a person has congestion, a runny nose, sneezing, an itchy nose, an itchy palate, or a sensation of mucus drip, the search often shifts toward allergic rhinitis, chronic rhinosinusitis, or postnasal drip. The Centers for Disease Control and Prevention (CDC) emphasizes that mucus drip, a sore throat, and a cough are typical of sinusitis, and a review of allergic rhinitis recommends always examining the back of the throat for signs of drip. [20]

The third step is a medication and behavioral history. It's important to determine whether the patient is taking an angiotensin-converting enzyme inhibitor, smoking, working in a dusty environment, experiencing high vocal strain, or sleeping with their mouth open. It's also important to determine whether the dryness has developed as a result of antihistamines, antidepressants, and other medications that can reduce salivation. When complaining of a sore throat, these details are often crucial. [21]

Reflux requires special caution. If heartburn, a sour taste, regurgitation, or a clear connection with food intake and body position are present, the likelihood of reflux is higher. However, if there is only a sore throat and cough without typical gastrointestinal symptoms, current guidelines do not recommend automatically treating this as reflux. In specialized cases, multi-level impedance-pH monitoring is considered the gold standard for diagnosis. [22]

Not everyone requires instrumental examinations. For a typical short-term viral presentation, observation and symptomatic treatment are usually sufficient. However, in cases of prolonged symptoms, red flags, hoarseness, unilaterality, dysphagia, cervical nodes, or suspected laryngeal pathology, endoscopic evaluation is indicated. The British Thoracic Society also notes that in protracted cases, laryngoscopy and additional investigations may be required if the initial examination and trial of therapy fail to explain the symptoms. [23]

Table 4. How is a sore throat usually diagnosed?

Stage	What is being clarified?	Why is this necessary?
Anamnesis	Duration, seasonality, connection with food, night, conversation, smells	Allows to identify the probable mechanism
Nasal symptoms	Runny nose, congestion, itching, mucus drainage	Looking for rhinitis, sinusitis, postnasal drip
Drug history	Angiotensin-converting enzyme inhibitors and other drugs	They are looking for a medicinal cause and dry mucous membranes
Evaluation of reflux symptoms	Heartburn, regurgitation, relationship with body position	Helps to understand whether there is reason to think about reflux
Examination and endoscopy as indicated	Oropharynx, larynx, neck	Needed for long-term, one-sided and alarming symptoms
Additional research	Impedance-pH monitoring, related consultations	Used in complex and unclear cases

Table based on: NICE, British Thoracic Society, European consensus on laryngopharyngeal reflux, NHS Scotland.[24]

Treatment: not for the sore throat in general, but for the specific reason

If the symptom is associated with acute viral irritation of the mucous membrane, treatment is usually supportive. NICE recommends explaining that acute sore throat and similar inflammatory symptoms often self-limited within about a week, advising adequate fluid intake, and using paracetamol or ibuprofen for pain and fever. Antibiotics are not necessary in most such cases. For a pure sore throat without a high fever and no signs of a bacterial process, this logic is even more relevant. [25]

When symptoms are caused by postnasal drip, allergic rhinitis, or chronic rhinosinusitis, nasal treatment is key. The UK National Health Service recommends avoiding triggers, using antihistamines, saline rinses, and intranasal steroids for allergic rhinitis. The British Thoracic Society recommends a combination of intranasal steroids and saline rinses for at least 6 weeks for patients with chronic rhinosinusitis symptoms, rather than prescribing antibiotics for the occasional tickle. [26]

If the primary problem is dry mucous membranes and mouth breathing, treatment is based on eliminating the drying mechanism. It is necessary to restore nasal breathing, correct dehydration, review medications that dry the mucous membranes, and reduce nighttime mouth breathing if it is associated with nasal congestion. In this group, everyday and behavioral measures are often more effective than any lozenges. [27]

If a drug-related cause is suspected, the most important thing is not to suppress the symptom but to reconsider the treatment. A dry cough and a persistent scratchy sensation in the throat associated with angiotensin-converting enzyme inhibitors have long been known. The National Kidney Foundation estimates that the risk of such a cough is approximately 10% with these medications and approximately 3% with angiotensin receptor blockers. The British Thoracic Society recommends discontinuing angiotensin-converting enzyme inhibitors in patients with chronic cough, regardless of whether a connection seems obvious. [28]

Management of reflux-associated symptoms has become more stringent. In the presence of typical heartburn, the British Thoracic Society allows a short trial course of a proton pump inhibitor for approximately 1 month, with discontinuation if there is no effect. The 2024 European Consensus recommends basing empirical treatment on diet, stress reduction, and agents that target both acid and alkaline reflux, with proton pump inhibitors reserved for patients with confirmed acid reflux and signs of gastroesophageal reflux. For isolated irritation without typical symptoms, automatic prescription of these drugs is considered a weak strategy. [29]

In some patients, laryngeal hypersensitivity and habitual throat clearing play a leading role. In this case, constant mechanical trauma to the larynx perpetuates the symptom. Official materials from the UK National Health Service describe conditions such as sensory dysfunction of the larynx, where speech therapy, trigger control, throat-clearing suppression techniques, and cough hypersensitivity management are helpful. This group of patients is particularly prone to long, ineffective courses of medication without lasting effect. [30]

Table 5. Treatment depending on the cause

Cause	The basic approach
Acute viral irritation	Fluids, symptomatic relief, usually without antibiotics
Allergic rhinitis	Avoidance of triggers, antihistamines, intranasal steroids, saline rinses
Chronic rhinosinusitis and postnasal drip	Saline irrigation and intranasal steroids; if symptoms persist, referral to an otolaryngologist
Mouth breathing and dry mucous membranes	Relief from nasal congestion, correction of dryness and dehydration, revision of medications
Medicinal cause	Discussion of discontinuation or replacement of angiotensin-converting enzyme inhibitor
Confirmed or probable reflux contribution	Diet, stress reduction, personalized anti-reflux tactics
Laryngeal hypersensitivity	Speech and behavioral methods, trigger control

Table based on: NICE, NHS, British Thoracic Society, National Kidney Foundation, European consensus on laryngopharyngeal reflux. [31]

Prevention and prognosis

Prevention depends on the cause, but almost always involves controlling triggers. For nasal and allergic causes, this includes reducing exposure to allergens, treating rhinitis, and maintaining nasal patency. For people with chronic dry throat, this includes drinking enough fluids, quitting smoking, reducing dust, and using a more gentle voice. For patients with a likely reflux cause, this includes controlling body weight, late meals, and individual food triggers. [32]

The key preventative measure for postnasal drip is to avoid neglecting nasal conditions. When chronic congestion becomes a permanent part of life, a person begins to breathe through their mouth, and mucus from the nasopharynx constantly irritates the back of the throat. This is why treating rhinitis and sinusitis is more important than endless lozenges and topical antiseptics. [33]

For patients with prolonged throat clearing and a sensitive larynx, preventing this self-perpetuating cycle is crucial. The more frequently a person clears their throat, the greater the mechanical irritation and the more persistent the feeling of "something's in the way." Prevention involves teaching alternative strategies, gentle swallowing, breath control, and reducing sensory overload of the larynx. [34]

The prognosis is favorable in most cases if the cause is correctly identified. Viral irritation of the mucous membrane resolves spontaneously, allergic and nasal components respond well to topical therapy, drug-induced irritation is usually eliminated after treatment adjustments, and dryness subsides after eliminating mouth breathing and dehydration. The most difficult cases are those where the "throat in general" is treated for months without identifying the actual mechanism of the symptom. [35]

The main risk is not the sore throat itself, but missing a serious cause. Therefore, the best prognosis is for patients who notice red flags early: a duration of more than 3 weeks, one-sidedness, dysphagia, hoarseness, ear pain, and neck swelling. In this situation, time is not on the side of waiting. [36]

FAQ

Can you have a sore throat without an infection?

Yes. In practice, this is a very common situation. A sore throat is often associated with allergic rhinitis, postnasal drip, mouth breathing, dry mucous membranes, reflux, medications, and laryngeal hypersensitivity. The absence of fever and severe pain makes infection less likely. [37]

Is it true that it is almost always reflux?

No. Current guidelines emphasize that throat symptoms alone do not confirm laryngopharyngeal reflux. Without typical heartburn and other characteristic signs, automatic prescription of proton pump inhibitors is considered a weak strategy. [38]

When should you think about your nose and not your throat itself?

When a sore throat is accompanied by congestion, mucus drainage, sneezing, itching in the nose, seasonality of symptoms, or a feeling of constantly having to clear your throat, the source of the problem is often in the nasal cavity and nasopharynx, not the pharynx itself. [39]

Can the medication cause a constant tickling sensation in the throat?

Yes. A classic example is angiotensin-converting enzyme inhibitors. They can cause a dry, irritating cough and a scratchy sensation in the throat, which disappears after switching medications. [40]

When should you urgently see a doctor?

Urgent care is needed for difficulty breathing, stridor, salivation, trismus, rapidly increasing pain, unilateral neck swelling, and a severe general condition. This is no longer a typical "scratchy throat" but a potentially dangerous scenario. [41]

How long can the symptom be observed at home?

A short-term sore throat associated with a cold can usually be observed for a few days. However, if the symptom persists for more than three weeks, especially if it is one-sided, accompanied by pain when swallowing, hoarseness, ear pain, or a cervical lump, prompt diagnosis is necessary. [42]

Why do I constantly want to clear my throat, even though there is almost no phlegm?

This occurs with postnasal drip, dry mucous membranes, and laryngeal hypersensitivity. The larynx begins to perceive even minor irritants as a signal to clear the throat, and the clearing itself further maintains the irritation. [43]

Do antibiotics help?

Usually not. If the symptom is due to a viral infection, allergy, mucus retention, dryness, reflux, or medication, antibiotics won't solve the problem. They are only needed in a limited number of infectious situations where there is compelling reason to suspect or confirm a bacterial process. [44]