One-sided throat pain during swallowing usually points to an infection or inflammatory process that has settled unevenly, with peritonsillar abscess being one of the most recognized causes of distinctly unilateral discomfort. But the list of possibilities extends well beyond a simple sore throat. Some causes are common and self-limiting, while others are rare enough that even clinicians can initially miss them. The fact that the pain is on one side, and that swallowing triggers or worsens it, actually narrows the diagnostic picture in useful ways.
Peritonsillar Abscess
If your right-sided throat pain came on over a few days and is getting steadily worse, peritonsillar abscess is one of the first things a doctor will consider. This happens when an infection near the tonsil forms a pocket of pus between the tonsil and the surrounding tissue. It almost always affects just one side. Along with severe pain on swallowing, the hallmarks include fever, difficulty opening the mouth fully, a muffled or “hot potato” voice, drooling, and visible displacement of the tonsil toward the midline of the throat. The uvula often shifts away from the affected side.
Peritonsillar abscess tends to develop as a complication of untreated or poorly treated tonsillitis. It is most common in young adults and adolescents but can occur at any age. Treatment typically involves draining the abscess, either with a needle or a small incision, along with antibiotics. Left untreated, the infection can spread into deeper tissue layers of the neck, which is a genuinely dangerous progression.
Other Deep Neck Infections
The throat is surrounded by several tissue compartments, and when infection gets into any of them, the result is a deep neck space infection. Two types are especially relevant to one-sided throat pain. Retropharyngeal abscess, which forms behind the back wall of the throat, typically causes fever, sore throat, neck pain, and painful swallowing. Parapharyngeal space infections, which develop alongside the throat, cause a similar picture but also tend to produce neck swelling and restricted jaw opening.
These infections can start from dental infections, tonsillitis, or even minor mucosal tears. They are less common than peritonsillar abscess but more dangerous because of the neck’s anatomy; infection in these spaces can track downward toward the chest. The pain is often one-sided early on, before the infection has a chance to spread. If you have severe throat pain with neck swelling, stiffness, or difficulty breathing, this warrants emergency evaluation.
Herpes Zoster in the Throat
Shingles does not only affect the skin. When the varicella-zoster virus reactivates in certain cranial nerves, it can produce painful blisters inside the throat on just one side. One case report describes reactivation in the vagus nerve leading to painful swallowing, voice changes, and difficulty swallowing, with blisters confined to one half of the larynx and epiglottis. The patient’s pain resolved within a month on antiviral medication, though some swallowing difficulty lingered.
What makes laryngeal shingles tricky is that the characteristic skin rash may never appear. Without visible blisters on the outside, the diagnosis depends on a scope examination of the throat. Another reported case involved a woman with persistent throat pain and cough for over two months before white ulcerated lesions were found on one side of her epiglottis and diagnosed as laryngeal herpes zoster. If you have severe one-sided throat pain and your doctor cannot see an obvious cause on a standard exam, shingles inside the throat is worth considering, especially if you are middle-aged or older.
Subacute Thyroiditis Disguised as a Sore Throat
This is one of the more commonly missed diagnoses behind one-sided throat pain. Subacute thyroiditis is an inflammatory condition of the thyroid gland, and because the thyroid sits just below and to the sides of the throat, the pain can feel exactly like a pharyngeal problem. A case series of 32 patients whose primary complaint was one-sided throat pain found that all of them ultimately had subacute thyroiditis. These patients, mostly women aged 28 to 52, reported pharyngeal pain lasting anywhere from a week to three months before the correct diagnosis was made.
Subacute thyroiditis often follows a viral upper respiratory infection. The pain may radiate to the ear or jaw, and the affected side of the neck can feel tender when pressed. The thyroid gland may be slightly enlarged. What typically gives it away is bloodwork: inflammatory markers are elevated, and thyroid hormone levels are often temporarily high because inflamed thyroid cells leak stored hormone into the bloodstream. If you have been treated for a sore throat that is not improving, and especially if the pain seems to be in the lower part of your throat or neck, ask about thyroid inflammation.
Eagle Syndrome and an Unusually Long Bone
Behind the ear, a small bony projection called the styloid process anchors several muscles and ligaments. In most people it is about two to three centimeters long and causes no trouble. In some people, it grows abnormally long or the ligament attached to it calcifies, and the elongated structure can press against the throat, nerves, or blood vessels nearby. This is called Eagle syndrome.
Eagle syndrome produces two somewhat different clinical pictures. One involves pain in the throat on one side that radiates to the ear and worsens with swallowing. The other involves headache and neck pain from compression of nearby blood vessels and nerves. One case report documented a styloid process measuring nearly 15 centimeters, roughly five times the normal length, in a patient who developed neck pain when swallowing. The diagnosis is typically made with a CT scan, and treatment involves surgically shortening the styloid process or removing the calcified ligament.
Eagle syndrome is considered a form of glossopharyngeal neuralgia, and it tends to show up in older adults. In some patients, the condition is managed with repeated nerve blocks rather than surgery, which can provide relief for patients who are not surgical candidates.
Glossopharyngeal Neuralgia Without Eagle Syndrome
Even without a structural abnormality like an elongated styloid process, the glossopharyngeal nerve can become a source of severe one-sided throat pain. Glossopharyngeal neuralgia is rare, but it produces a distinctive pattern: sudden, intense bursts of pain in the back of the throat, the base of the tongue, the tonsil area, or just below the angle of the jaw, often triggered by swallowing, talking, or yawning. The pain typically lasts seconds to a couple of minutes and can be excruciating.
The condition is sometimes compared to trigeminal neuralgia, its more famous cousin that affects the face. Between episodes, the person may feel completely fine, which can make the diagnosis confusing if the attacks are infrequent. Treatment usually involves medications originally developed for seizures, which calm overactive nerve signaling. In refractory cases, surgical options exist to decompress or selectively cut the nerve.
Hyoid Bone Syndrome
The hyoid is a small horseshoe-shaped bone in the front of the neck, just above the Adam’s apple, that supports the tongue and helps with swallowing. In some people, the greater horn of the hyoid bone becomes a source of pain, particularly during swallowing. The pain is felt in the region of the hyoid and can radiate to the ear, face, lower jaw, or into the throat itself. Because the hyoid is not symmetrical in everyone, and injuries or degenerative changes can affect one side more than the other, the pain may be distinctly one-sided.
Hyoid bone syndrome is diagnosed partly by reproducing the pain with direct pressure on the hyoid. It can follow neck trauma or develop without any clear cause. Treatment ranges from anti-inflammatory medications and local steroid injections to surgical removal of part of the hyoid in severe cases. It is one of those diagnoses that tends to be made only after more common causes have been ruled out.
When One-Sided Throat Pain Raises Concern for Cancer
Persistent unilateral sore throat is something head and neck cancer specialists pay attention to, and for good reason. A study of 85 patients who presented with a one-sided sore throat lasting more than four weeks found that about one in ten had a head and neck cancer. The cancers were found despite the patients having no obviously suspicious findings on initial examination in many cases.
This does not mean that everyone with right-sided throat pain for a few weeks has cancer. The overwhelming majority of one-sided sore throats are caused by infections, muscle strain, or one of the other conditions described above. But there are features that should prompt a more thorough evaluation: pain lasting more than four weeks without improvement, unexplained weight loss, ear pain on the same side with a normal-looking eardrum, a new lump in the neck, voice changes, or difficulty swallowing that progressively worsens. Smoking and heavy alcohol use increase the risk, as does infection with certain strains of human papillomavirus. If your throat pain on one side has been hanging around for more than a month, getting scoped by an ear, nose, and throat specialist is a reasonable step.
Foreign Bodies and Mechanical Injury
Sometimes the explanation is straightforward: something scratched or got stuck in your throat. Fish bones, small bone fragments, and poorly chewed food are common culprits that can lodge in the tonsil, the base of the tongue, or the upper part of the esophagus. Even after the object passes or is removed, a scratch in the throat lining can cause pain on one side for several days, especially during swallowing. The sensation of something still being there even after an object has passed is very common and can persist for a surprisingly long time.
Medical procedures can produce a similar effect. After general anesthesia involving a breathing tube, one-sided sore throat is common. The tube is inserted through the mouth and past the vocal cords, and the process can cause mechanical injury to the throat lining. Inserting the scope used to guide the tube, the tube itself contacting the back wall of the throat, and coughing during removal can all contribute to mucosal damage. Post-intubation throat pain is usually mild and resolves within a few days, but it can occasionally be severe enough to make swallowing uncomfortable for a week or more.
How a Deviated Nasal Septum Can Affect Your Throat
This one surprises most people. When the wall between your nasal passages is crooked enough to block airflow on one side, you end up breathing more through your mouth or channeling air unevenly through the throat. Over time, this asymmetric airflow can dry out and irritate one side of the throat more than the other. A study comparing throat symptoms in adults with significant nasal septum deviation found that these patients had substantially higher throat symptom scores compared to people without deviation. After surgical correction of the septum, those scores dropped significantly.
If you notice that your right-sided throat discomfort is worse in the morning, worse in dry environments, or seems to come and go rather than following an infectious pattern, it is worth considering whether nasal obstruction might be playing a role. This is especially true if you have a known history of a deviated septum, chronic nasal congestion on one side, or a tendency to breathe through your mouth at night.
Epiglottitis in Adults
Epiglottitis, an infection of the flap of tissue that covers the windpipe during swallowing, is usually associated with children, but it occurs in adults as well and can be life-threatening. In adults, it tends to progress more slowly than in children, but the core danger is the same: the swollen epiglottis can block the airway. A reported case of adult epiglottitis involved a 69-year-old woman who presented with difficulty swallowing and neck swelling. The pain may initially seem one-sided depending on where the swelling is most pronounced.
Adult epiglottitis is considered a medical emergency because of the potential for sudden airway compromise. Warning signs include severe sore throat with pain out of proportion to what the doctor sees on a standard exam, drooling, difficulty swallowing your own saliva, muffled voice, and a preference for sitting upright and leaning forward. If swallowing becomes so painful that you cannot manage your own saliva, do not wait to see if it improves.
Sorting Through the Possibilities
The timeline and accompanying symptoms do most of the diagnostic work. Infections like peritonsillar abscess and deep neck infections come on over days, produce fever, and make the person feel systemically unwell. Nerve-related pain like glossopharyngeal neuralgia is episodic and lightning-fast. Structural causes like Eagle syndrome and hyoid bone syndrome tend to be chronic and reproducible with specific movements. Subacute thyroiditis often follows a cold and comes with subtle thyroid symptoms. A foreign body or scratch has a clear onset tied to a meal or procedure.
One useful distinction is whether the pain is truly in the throat or in the neck alongside the throat. The throat and the structures surrounding it are packed closely together, and pain from the thyroid, a lymph node, a salivary gland, or even a strained neck muscle can all be perceived as throat pain during swallowing because swallowing moves everything in the area. Pressing gently on the outside of the neck to see if the pain is reproducible from the outside can sometimes help narrow things down before you even see a doctor.
For most people, one-sided throat pain that comes on with a cold or after eating something sharp will resolve on its own within a week or so with supportive care: staying hydrated, using over-the-counter pain relief, and giving the tissue time to heal. The situations that call for prompt medical attention include pain lasting more than two weeks without improvement, fever with visible neck swelling, inability to swallow liquids or your own saliva, difficulty breathing, and pain that started suddenly with a stabbing character and keeps recurring in short bursts. A sore throat that stays stubbornly on one side, especially if it outlasts a typical viral infection, deserves a closer look than one that is diffusely uncomfortable on both sides.