Sore Throat: Causes, Relief and When to See a Doctor

What causes a sore throat

Viral infections (most cases)

• common cold and other upper respiratory viruses
• flu and COVID-19
• infectious mononucleosis (glandular fever): very sore throat, swollen tonsils with white coating, swollen neck glands and exhaustion, mostly in teens and young adults
• adenovirus: sore throat with red eyes, especially in children
• hand, foot and mouth disease and herpangina: painful mouth and throat blisters in young children

Clues for a virus: cough, runny nose, hoarseness, red eyes or mouth ulcers.

Strep throat and other bacteria

Strep throat is caused by group A Streptococcus. Clues:

• sudden onset of throat pain and pain on swallowing
• fever
• swollen, tender glands at the front of the neck
• red, swollen tonsils, often with white patches
• tiny red spots on the roof of the mouth
• no cough or runny nose
• in children: headache, stomach ache, nausea or vomiting
• sometimes a fine red rash (scarlet fever)

Strep is uncommon in children under 3 and in adults over 45. Other bacteria, including gonorrhea after oral sex, can rarely cause throat infections.

Non-infectious causes

• dry air and mouth breathing, especially at night
• post-nasal drip from allergies or sinusitis
• acid reflux (GERD or silent reflux): a raw throat, often in the morning, with throat clearing and hoarseness
• smoking, vaping and pollution
• voice strain from shouting or singing
• a foreign body, such as a fish bone
• rarely, throat cancer: a persistent one-sided sore throat, ear pain, hoarseness, or a neck lump in a smoker or drinker

Strep throat vs a viral sore throat

Doctors use scoring systems (the Centor or McIsaac criteria) based on these features to decide who needs testing. You cannot tell for sure by looking: a test is needed.

Sore throat on one side

Pain on one side can come from:

• peritonsillar abscess (quinsy): severe one-sided pain, a muffled voice, drooling, difficulty opening the mouth; needs drainage
• one-sided tonsillitis or a swollen lymph node
• a dental infection or ear problem causing referred pain
• a foreign body or a scratch
• post-nasal drip draining down one side
• rarely, a tumor, if persistent for more than 3 weeks

How a sore throat is diagnosed

A doctor will look at your throat, feel your neck glands and check for a rash and enlarged spleen. Tests:

• rapid strep test: a throat swab with results in minutes
• throat culture: done if a child's rapid test is negative but strep is still suspected
• mono test or blood count if mono is likely
• COVID-19 or flu test when relevant

Sore throat relief

What helps the pain

• Pain relievers: acetaminophen (paracetamol) or ibuprofen. Follow the label dose. Do not give aspirin to children or teenagers.
• Warm drinks (tea with honey, broth) or cold foods (ice pops, ice chips, smoothies).
• Honey soothes the throat and cough in adults and children over 1 year. Never give honey to babies under 12 months.
• Salt water gargle: half a teaspoon of salt in a cup of warm water, several times a day, for children old enough to gargle.
• Lozenges and throat sprays with a numbing agent, for adults and older children. Avoid lozenges in young children because of choking risk.
• Humidify the bedroom air and drink plenty of fluids.
• Rest your voice and avoid smoke.

When antibiotics are needed

Antibiotics treat strep throat. Penicillin or amoxicillin are first choice; alternatives exist for people with penicillin allergy. Take the full course, usually 10 days. They shorten symptoms slightly, prevent spread, and prevent rare complications such as rheumatic fever and abscess. You are no longer contagious after about 12 to 24 hours of antibiotics.

Antibiotics do not help viral sore throats, including mono. In mono, amoxicillin often causes a rash.

Steroids

A single dose of a steroid is sometimes given for severe throat pain or swelling, especially in mono with very large tonsils.

How long a sore throat lasts

• viral: 5 to 7 days, sometimes up to 10
• strep: improves within 1 to 3 days of antibiotics; 3 to 7 days without
• mono: throat pain for 1 to 2 weeks, tiredness for weeks to months

When tonsil removal is considered

Tonsillectomy may be recommended for children or adults with frequent, well-documented throat infections (for example, 7 or more in 1 year, 5 a year for 2 years, or 3 a year for 3 years), a peritonsillar abscess that recurs, or sleep-disordered breathing from large tonsils.

Frequently asked questions

How do I know if my sore throat is strep?

Strep is more likely with sudden throat pain, fever, swollen tender neck glands, white patches on the tonsils and no cough or runny nose. The only way to know is a rapid strep test or throat culture, which a doctor or many pharmacies can do.

How long does a sore throat last?

Most viral sore throats improve within 5 to 7 days. Strep throat improves within 1 to 3 days of starting antibiotics. See a doctor if your sore throat lasts more than a week, keeps coming back, or is severe.

What is the fastest way to cure a sore throat?

There is no instant cure for a viral sore throat, but pain relievers, salt water gargles, honey in warm drinks, cold foods, lozenges and humidified air ease pain quickly. If strep is confirmed, antibiotics speed recovery and stop the spread.

Why does my throat hurt on one side?

One-sided throat pain can come from tonsillitis, a swollen gland, a dental or ear problem, or a peritonsillar abscess. Severe one-sided pain with a muffled voice, drooling or trouble opening your mouth needs same-day care.

Can acid reflux cause a sore throat?

Yes. Stomach acid rising into the throat, especially at night, can cause a raw throat in the morning, frequent throat clearing, hoarseness and a lump-in-the-throat feeling. Avoiding late meals and raising the head of the bed often help.

When is a sore throat an emergency?

Get emergency help for difficulty breathing, drooling or being unable to swallow saliva, noisy breathing, swelling of the tongue or neck, or a child who is very unwell and sitting forward to breathe. These can mean a blocked airway.