Tonsillitis is common in young children and is frequently encountered by parents as a sore throat that makes swallowing painful, is accompanied by fever, and causes the child to refuse to eat. Most parents' primary concern is whether antibiotics are needed — and the answer depends on whether the cause is viral or bacterial, which is not always immediately clear from symptoms alone.
Understanding what tonsillitis is, how to tell whether it is likely to be viral or bacterial, and when to see a GP allows parents to manage tonsillitis appropriately — treating the symptoms while it runs its course for most viral cases, and ensuring bacterial cases are correctly identified and treated.
Healthbooq supports parents with evidence-based guidance on common childhood illnesses, including clear indicators for when symptoms warrant a GP visit.
What Tonsillitis Is
The tonsils are lymph tissue at the back of the throat that form part of the immune system's first line of defence against pathogens entering via the mouth and nose. Tonsillitis is inflammation of the tonsils — they become swollen, red, and tender, sometimes with pus-filled spots or a white coating on the surface.
The condition is most common in school-age children but is also seen in toddlers and preschoolers. In very young babies (under one year) it is relatively uncommon, and a sore throat with high fever in a baby should always be assessed by a doctor.
Viral vs Bacterial Tonsillitis
Viral tonsillitis accounts for around sixty to seventy percent of cases. It is most commonly caused by the same viruses that cause the common cold (rhinovirus, adenovirus) or, less commonly, Epstein-Barr virus (the cause of glandular fever). Viral tonsillitis does not benefit from antibiotics and is treated with supportive care: pain relief (paracetamol or ibuprofen at appropriate doses), fluids, and rest.
Bacterial tonsillitis — caused most often by Group A Streptococcus (Strep A) — accounts for the remaining third of cases. It is treated with penicillin (or amoxicillin), typically for ten days. Completing the full course is important because incomplete treatment of Strep A tonsillitis can, in rare cases, lead to complications including rheumatic fever.
Clinically, it can be difficult to distinguish viral from bacterial tonsillitis. Features more suggestive of bacterial infection include absence of cough, presence of pus on the tonsils (tonsillar exudate), swollen and tender glands in the neck (cervical lymphadenopathy), and high fever. Features more suggestive of viral infection include cough, runny nose, and mouth ulcers. The Centor and FeverPAIN scoring systems used by GPs use combinations of these features to estimate the probability of streptococcal infection. A throat swab can confirm bacterial infection and is often used when the clinical picture is uncertain.
Symptom Management
Regardless of the cause, the immediate priority is keeping the child comfortable and adequately hydrated. Paracetamol and ibuprofen (at appropriate doses for age and weight) relieve throat pain enough to allow the child to drink. Cold drinks and ice-cream or ice lollies can soothe the throat. Warm drinks (not hot) can also help.
If the child refuses to swallow fluids or develops audible difficulty breathing or swallowing, this is urgent and warrants same-day medical assessment: difficulty swallowing saliva or stridor (noisy breathing) can indicate peritonsillar abscess, which requires urgent treatment.
When to See a GP
A child with a sore throat and mild symptoms who is still drinking and has no breathing difficulty can generally be managed at home for the first two to three days. A GP visit is warranted if the fever is high and persistent (over 38°C for more than three days), the child is unable to swallow fluids, symptoms are worsening rather than improving after three to four days, there is excessive drooling or difficulty opening the mouth, or the parent is concerned.
Key Takeaways
Tonsillitis — inflammation of the tonsils at the back of the throat — is most commonly caused by viruses and resolves without antibiotics within a week. Bacterial tonsillitis (usually Group A Streptococcus) accounts for around a third of cases and does warrant antibiotic treatment. The clinical challenge is distinguishing viral from bacterial tonsillitis, which is not always possible without a throat swab. Complications of untreated bacterial tonsillitis are rare but include peritonsillar abscess and, with certain streptococcal strains, rheumatic fever — which is why completing the full antibiotic course matters when bacteria are confirmed.
