Sore throats can result in pain, a scratchy sensation, hoarseness, and burning when you swallow.

A persistent sore throat can recur multiple times, or it can be long term (chronic). A persistent sore throat can result from a variety of conditions, including a handful of potentially dangerous infections, so it’s important to pinpoint its cause as quickly as possible.

A number of conditions can trigger a persistent sore throat, including:

Allergies

When you have an allergy, your immune system is hyper-reactive to certain substances that are normally harmless. These substances are called allergens.

Common allergens include foods, certain plants, pet dander, dust, and pollen. You’re particularly susceptible to a persistent sore throat if you have allergies associated with things you breathe in (pollen, dust, synthetic fragrances, mold, and so forth).

The most frequent symptoms associated with these types of airborne allergies include:

  • runny nose
  • coughing
  • sneezing
  • itchy eyes
  • watery eyes

The postnasal drip from a runny nose and inflamed sinuses is the most likely cause of a sore throat due to allergies.

Postnasal drip

When you have postnasal drip, excess mucus drains from your sinuses into the back of your throat. This can lead to a persistent raw, sore, or scratchy throat. Postnasal drip can be triggered by weather changes, some medicines, spicy foods, a deviated septum, allergies, dry air, and more.

Besides sore throat, some of the symptoms of postnasal drip include:

  • no fever
  • bad breath
  • a sensation of needing to swallow or clear your throat all the time
  • coughing that worsens at night
  • nausea from the excess mucus in your stomach

Mouth breathing

If you breathe through your mouth chronically, particularly when you’re asleep, this can lead to a recurring sore throat. Most likely, you’ll experience it first thing in the morning when you wake up, and the soreness is likely to be relieved once you take a drink.

The symptoms of nighttime mouth breathing include:

Most of the time, mouth breathing is due to some kind of nasal obstruction that prevents you from breathing properly through your nose. This can include nasal congestion, sleep apnea, and enlarged adenoids or tonsils.

Acid reflux

Acid reflux, also known as heartburn, occurs when the lower esophageal sphincter (LES) has weakened and becomes unable to close tightly. Stomach contents then flow backward and up into the esophagus. Sometimes acid reflux can lead to a sore throat. If you’re having symptoms daily, it’s possible for them to cause persistent soreness.

Over time, the acid from your stomach can damage the lining of the esophagus and your throat.

Common symptoms of acid reflux include:

  • sore throat
  • heartburn
  • regurgitation
  • sour taste in your mouth
  • burning and discomfort (upper middle stomach area)
  • trouble swallowing

Tonsillitis

If you’re experiencing a prolonged sore throat and are unable to find relief, it’s possible you may have an infection like tonsillitis. Most often, tonsillitis is diagnosed in children, but people can get it at any age. Tonsillitis can be caused by bacterial infections or viruses.

Tonsillitis may recur (reappearing multiple times per year) and requires treatment with prescription antibiotics. Because there are multiple types of tonsillitis, symptoms are widely varied and can include:

  • difficulty swallowing or painful swallowing
  • a voice that sounds scratchy or hoarse
  • a severe sore throat
  • stiff neck
  • jaw and neck tenderness due to swollen lymph nodes
  • tonsils that appear red and swollen
  • tonsils that have white or yellow spots
  • bad breath
  • fever
  • chills
  • headaches

Mono

Another cause of sore throat and tonsillitis, mononucleosis (or mono for short) results from an infection by the Epstein-Barr virus (EBV). While mono can last up to two months, in most cases it’s mild and can be resolved with minimal treatment. Mono feels like having the flu, and its symptoms include:

  • sore throat
  • swollen tonsils
  • fever
  • swollen glands (armpits and neck)
  • headache
  • fatigue
  • muscle weakness
  • night sweats

It’s possible a person with mono might experience a persistent sore throat for the duration of the active infection.

Gonorrhea

Gonorrhea is a sexually transmitted infection (STI) caused by the bacterium Neisseria gonorrhoeae. You might think of an STI as something that only affects your genitals, but a gonorrhea infection in the throat can occur from unprotected oral sex.

When gonorrhea affects the throat, it typically only results in a red and persistently sore throat.

Environmental pollution

If you live in an area like a large city, it’s possible you could have a persistent sore throat from smog, a conglomeration of airborne pollutants. Especially on hot days, it can be dangerous to breathe smog. In addition to an irritated, sore throat, breathing smog can cause:

  • worsening of asthma symptoms
  • coughing
  • chest irritation
  • difficulty breathing
  • lung damage

Tonsil abscess

A peritonsillar abscess is a serious bacterial infection in the tonsil that can cause a persistent, severe sore throat. It can occur when tonsillitis haven’t been properly treated. A pus-filled pocket forms near one of the tonsils when infection breaks out of the tonsil and spreads to the surrounding tissue.

You may be able to see the abscess at the back of your throat, but it’s possible that it could be hidden behind one of your tonsils. Symptoms are usually similar to those of tonsillitis, though more severe. They include:

  • sore throat (usually worse on one side)
  • tender, painful, swollen glands in the throat and jaw
  • ear pain on the side of the sore throat
  • infection in one or both tonsils
  • difficulty opening the mouth fully
  • difficulty swallowing
  • difficulty swallowing saliva (drooling)
  • swelling of the face or neck
  • difficulty turning the head from side to side
  • difficulty tilting the head down (moving the chin to the chest)
  • difficulty tilting the head up
  • headache
  • muffled voice
  • fever or chills
  • bad breath

Smoking

Smoking and exposure to secondhand smoke can cause a scratchy or sore throat, along with worsened asthma, bronchitis, emphysema, and more.

In mild cases, the exposure to toxins in cigarette smoke leads to the sore throat. But smoking is also a risk factor of throat cancer, which can result in throat pain as well.

If your sore throat lasts longer than two days, contact your doctor for an examination. Reasons for a sore throat are easily diagnosed, and most are easily treated. But see a doctor or seek emergency treatment immediately if you experience:

  • severe pain that impairs eating, talking, or sleeping
  • high fever over 101˚F (38˚C)
  • intense, severe pain on one side of your throat, along with swollen glands
  • trouble turning your head

If you have a persistent sore throat that isn’t due to an infection, it’s possible to treat your symptoms at home. You can relieve symptoms of a sore throat by:

  • sucking on a lozenge or piece of hard candy
  • drinking plenty of water
  • eating popsicles or chipped ice
  • running a humidifier if the air in your house is dry
  • irrigating your nasal passages with a neti pot or bulb syringe
  • giving yourself a steam treatment (breathing steam from a bowl of hot water or in the shower)
  • sipping warm broth or tea
  • adding honey and lemon to warm tea or water
  • sipping juice with a small amount of diluted apple cider vinegar
  • taking a pain reliever like acetaminophen (Tylenol), ibuprofen (Advil), or naproxen (Alleve)
  • gargling with salt water
  • limiting exposure or removing allergens from your environment
  • taking over-the-counter allergy or cold medication
  • not smoking

In some cases, your doctor will need to intervene with treatment solutions to help you find relief:

  • If your sore throat is due to acid reflux, your doctor might prescribe antacid medication to relieve your symptoms.
  • Your doctor could prescribe a prescription allergy medicine, allergy shots, or nasal spray if seasonal allergies are causing your sore throat.
  • For tonsillitis, your doctor will prescribe a course of antibiotics to treat the infection.
  • Your doctor might prescribe steroid medication to relieve the swelling and pain of an EBV infection if you have mono.

For more severe conditions like an advanced infection or peritonsillar abscess, you may have to be hospitalized to receive antibiotics through a vein (intravenously). In some cases, an abscessed tonsil requires surgery. Chronically swollen tonsils that impair breathing or sleeping may need to be surgically removed.

Most of the time, a persistent sore throat can go away on its own within a few days to a week, depending on its cause and treatment. Throat infection symptoms may persist for up to seven days, even with treatment. People with mono might experience a sore throat for up to two months.

If you require tonsillectomy surgery or surgery to treat an abscess, you should expect to experience some pain in your throat during the recovery period.