Throat Infection: Symptoms, Treatment, Antibiotics

Quick answer

Mostly viral; antibiotics only for bacterial infection

Viruses cause 70–85% of throat infections in adults and about 60–70% in children. Typical features are sore throat, pain on swallowing, fever, swollen glands and sometimes cough, runny nose and hoarseness (which point to a virus). Group A strep is the commonest bacterial cause and is confirmed with a rapid test or culture. Treatment is pain relief, fluids and rest; antibiotics (usually penicillin or amoxicillin for 10 days) are used for confirmed bacterial infection. See a doctor for severe symptoms, difficulty swallowing or breathing, symptoms beyond a week or recurrent infections.

Important. Drooling, inability to swallow saliva, trouble breathing, a muffled “hot potato” voice, severe pain on one side with difficulty opening the mouth, a stiff neck, or a rash with fever needs urgent medical assessment.

What is a throat infection?

The term covers infections of the pharynx (pharyngitis), tonsils (tonsillitis) and sometimes the voice box (laryngitis). Infectious agents reach the throat through droplets or contact, and the lining responds with inflammation, causing pain, redness and swelling. Throat infections are among the most common reasons for visiting a doctor, particularly in children and teenagers.

Viral and bacterial causes

Viruses: rhinovirus, coronavirus (including SARS-CoV-2), adenovirus, influenza, Epstein–Barr virus (glandular fever), herpes simplex and others.
Group A Streptococcus (strep throat): about 20–30% of sore throats in children and 5–15% in adults.
Other bacteria, rarer: groups C and G streptococci, Arcanobacterium, gonorrhoea, chlamydia and diphtheria.
Fungal infection (thrush) in some people using inhaled steroids or with weak immunity.
Non-infectious sore throats from allergy, reflux, smoke and dry air can mimic infection.

Symptoms

Sore, scratchy or burning throat; pain on swallowing.
Red throat and tonsils, sometimes with white patches or pus.
Fever, headache, tiredness and general aches.
Tender, swollen glands in the neck.
Bad breath, hoarse voice and ear pain (referred pain).
A runny nose, cough and sneezing suggest a virus.
In young children: poor feeding, drooling and irritability.

Telling viral from bacterial

The look of the throat cannot reliably distinguish them. Doctors use symptom scores (Centor or McIsaac), which favour strep when there is fever, tonsil exudate, tender front neck glands and no cough. A rapid antigen test or throat swab confirms strep. Mouth ulcers, conjunctivitis, hoarseness and nasal symptoms point to a virus. See strep throat and tonsillitis treatment.

Treatment at home

Pain and fever: paracetamol (acetaminophen) or ibuprofen at the recommended doses.
Fluids: drink plenty of water, warm drinks or cold treats such as ice lollies.
Soft food and honey in warm drinks (over one year).
Salt-water gargles and lozenges for adults and older children.
Rest while you have a fever; humidify the air.
Avoid smoking, alcohol and spicy foods.
Hygiene: wash hands and avoid sharing cups or cutlery.

When antibiotics are needed

Antibiotics are advised for confirmed or strongly suspected group A strep, for peritonsillar abscess and for people at higher risk of complications. First choice is penicillin V or amoxicillin for 10 days, with alternatives for allergy. For viral infections, they do not shorten the illness and carry side effects such as diarrhoea, rash and thrush, plus the long-term cost of antibiotic resistance. Taking an antibiotic without a test or using leftover tablets is not advised.

How long does it last?

Viral throat infections usually improve within 3–7 days. Bacterial infections respond within 2–3 days of antibiotics, with full recovery in about a week. Glandular fever can cause a severe sore throat for up to two weeks, with fatigue lasting weeks or months. A sore throat lasting more than a week or one that worsens after initially improving needs review.

Possible complications

Peritonsillar or retropharyngeal abscess: a collection of pus needing drainage.
Ear and sinus infections.
Acute rheumatic fever (rare, after untreated strep) and post-streptococcal kidney inflammation.
Dehydration, especially in children.
Airway swelling, very rare, in epiglottitis or deep neck infections.

Preventing and limiting spread

Wash hands often and cover coughs and sneezes.
Avoid sharing drinks, cutlery and toothbrushes.
Stay home while feverish; children with strep can return 12–24 hours after starting antibiotics.
Do not smoke and avoid smoky environments.
Keep vaccinations current (flu, COVID-19).

When to see a doctor

High fever with a severe sore throat and no cough.
Difficulty swallowing, breathing or opening the mouth, or drooling (urgent).
Symptoms longer than a week, or recurring infections.
A weak immune system, diabetes or heart valve disease.
A rash, joint pain or dark urine after a sore throat.
One-sided swelling or a neck lump.

Three common situations

Sore throat with cough and runny nose: almost certainly viral; supportive care.

Child with fever, white-spotted tonsils and no cough: see a doctor for a strep test.

Adult with severe one-sided throat pain and a muffled voice: possible abscess; seek urgent care.

Throat infections in children

Children under three rarely have strep throat; their sore throats are usually viral. Older children often present with fever and stomach ache. Offer fluids and cold treats, use age-appropriate paracetamol or ibuprofen and avoid lozenges in under-sixes. Seek advice if a child refuses to drink, drools, has trouble breathing, seems very unwell or has a sore throat with a rash, since scarlet fever and other conditions need treatment.

Key points to remember

Most throat infections are viral and clear up by themselves. Treat the symptoms, get a test when the pattern suggests strep and seek help for warning signs. Our ENT team can examine your throat and advise on treatment.

This guide is for general information and does not replace an assessment by your own doctor or ENT specialist.

Questions about throat infections

These answers are general information and do not replace an examination or individual medical advice.

How can I tell if a throat infection is viral or bacterial?

You cannot be sure from appearance; cough and runny nose suggest a virus, while fever, white patches and tender glands without cough suggest strep. A test confirms it.

Do I need antibiotics?

Only for confirmed bacterial infections such as strep throat.

How long is a throat infection contagious?

While symptoms last; strep is generally non-contagious 12–24 hours after starting antibiotics.

What helps a throat infection at home?

Pain relief, fluids, rest, honey, gargles and humid air.

Can a throat infection spread to the ears?

Yes; ear and sinus infections are possible complications.

When should I go to the emergency department?

For drooling, trouble breathing or swallowing, a muffled voice or severe one-sided pain.

Sources

This guide is for general information and does not replace medical advice. How a problem is diagnosed and treated depends on your examination and medical history. If you think you have an emergency, contact your local emergency services.