Tonsillitis vs strep throat: how the two terms relate

Tonsillitis and strep throat are not two competing diagnoses. Tonsillitis is a description of what is happening: the NHS defines it as an infection of the tonsils at the sides of the throat. Strep throat is a description of one possible cause: the NHS lists it as a bacterial throat infection that sits alongside tonsillitis, laryngitis and glandular fever among the causes of a sore throat. Put simply, strep throat can cause tonsillitis, but most tonsillitis is not strep throat.

That is why the two words are often used together and why the answer to which one you have depends on a test rather than on how the throat looks. The NHS tonsillitis page says that a GP can usually tell it is tonsillitis by asking about symptoms and looking in the throat, but that a swab may be used to find out whether bacteria are the cause.

Tonsillitis is a common childhood illness that teenagers and adults can get too. The tonsils become red and swollen. The NHS lists a sore throat, problems swallowing, a high temperature, coughing, a headache, feeling and being sick, earache and tiredness. More severe symptoms can include swollen, painful glands in the neck, pus-filled spots or white patches on the tonsils and bad breath.

Strep throat is a bacterial throat infection. NHS inform lists swollen glands in the neck, discomfort when swallowing and tonsillitis as features you may have with it. This means the picture of strep throat often includes tonsillitis, which is why the labels overlap so much. Most sore throats are not strep throat: the NHS says sore throats are usually caused by viruses, such as colds or flu, or by smoking, and only very occasionally by bacteria.

The table sets out how the NHS and NHS inform describe each term. Because strep throat is a cause rather than a separate organ problem, the comparison is mostly about what the word tells you.

You cannot reliably tell a viral sore throat from a bacterial one from the symptoms alone, and the NHS pages do not give a checklist that does. What they describe is a process. A doctor asks about your symptoms and looks in your throat, and may then take a swab by wiping a cotton bud over the back of the throat to see whether bacteria are causing the infection. The NHS adds that a blood test for glandular fever may be done if symptoms are severe or will not go away, because glandular fever can look similar.

NHS inform lists glandular fever, laryngitis and irritation from smoke, reflux or allergies among other things that cause a sore throat. If your symptoms do not fit the pattern of a short throat infection, a clinician may look for one of these.

For viral tonsillitis, which the NHS says is what most children and adults have, treatment is rest, cool drinks, paracetamol or ibuprofen (aspirin should not be given to children under 16) and, for adults and older children, gargling with warm salty water. A pharmacist can suggest lozenges, throat sprays or antiseptic solutions, although the NHS notes there is little proof that sprays help.

For bacterial tonsillitis, the NHS says a GP may prescribe antibiotics. The NHS sore throat page says a pharmacist can give the same antibiotic treatment as a GP if it is needed, for people aged 5 or over, while a child under 5 should be seen by a GP. NHS inform adds that antibiotics are not usually prescribed for a sore throat even when it is bacterial, because they are unlikely to make you feel better any quicker and have unpleasant side effects. This is why a clinician weighs the symptoms rather than treating every sore throat with antibiotics.

The NHS notes that having tonsils removed is very rarely needed and is usually only considered for severe tonsillitis that keeps coming back.

The NHS says to see a GP if tonsillitis symptoms do not go away within 1 week or if you keep getting throat infections. It says to get help from NHS 111 now if you have pus-filled spots on your tonsils or a sore throat so painful that it is difficult to eat or drink. In the sore throat advice it adds a very high temperature, signs of dehydration such as peeing less than usual, and a weakened immune system, for example because of diabetes or chemotherapy.

Some symptoms are emergencies. The NHS tonsillitis page lists a severe sore throat that quickly gets worse, swelling inside the mouth and throat, difficulty speaking, being unable to swallow, difficulty breathing and difficulty opening the mouth as signs of quinsy, a pus-filled abscess behind the tonsil, and says to call 999 or go to A&E. The sore throat page also lists drooling and a high-pitched sound when breathing (stridor). Do not drive yourself to A&E.

The NHS says tonsillitis itself is not contagious, but most of the infections that cause it, such as colds and flu, are. It suggests staying at home if you have a high temperature or do not feel well enough to do your usual activities, using tissues when you cough or sneeze and washing your hands afterwards.