Tonsil Stones: Causes, Bad Breath and How to Get Rid of Them

The palatine tonsils are part of the throat's immune system and have a surface folded into deep pits, the crypts. Shed epithelial cells, mucus, food remnants and bacteria collect in these crypts. When the material is not washed out by saliva and throat movements, it gradually thickens, forms a bacterial biofilm and may calcify into a stone. This account of the mechanism is generally accepted in the ENT literature, although the exact sequence of events has not been fully clarified.

The role of bacteria is often oversimplified. A multi-institutional study of adults after tonsillectomy (Arvisais-Anhalt et al., 2020) found that Actinomyces is common in tissue with stones but also in tonsils without them. The authors conclude that Actinomyces is probably not the main driver of stone formation and that treatment aimed at this organism may not be effective. This matters for patients who expect antibiotics to get rid of stones: there is no evidence that antibiotic therapy prevents them.

The mechanism points to the features of anatomy that favour stones: deep, extensive crypts, enlarged or scarred tonsils, recurrent infections. People with stones often have a history of tonsillitis or chronic inflammation, though this is not a rule. After a tonsillectomy the palatine tonsils are gone, which removes the problem at its source, although stones can also form in the lingual tonsil at the base of the tongue.

The practical conclusion: most tonsil stones are an incidental finding and need no treatment. Symptoms, when present, are usually mild and involve a few recurring complaints.

Ear pain with throat symptoms can result from the nerve supply that links these areas and does not have to mean an ear infection. Fever, worsening pain on swallowing or difficulty opening the mouth are not typical of stones alone; if such symptoms occur, another cause has to be sought.

A link is plausible, but not as universal as advertising suggests. In the classification of halitosis, odour of tonsillar origin belongs to so-called airway halitosis, and an ENT review notes that, by some reports, only about 3% of objectively confirmed halitosis has a tonsillar cause. The great majority of bad breath comes from the mouth: the tongue surface, gum disease, caries.

What follows? Tonsil stones can be a real source of volatile sulphur compounds, especially in people with chronic caseous tonsillitis, but in most people with bad breath the culprit is the mouth. That is why the 2014 review by Ferguson et al. advises first ruling out oral causes (for example by tongue scraping), and considers tonsil procedures contraindicated for subjective halitosis (when the person smells an odour that others do not), for a non-tonsillar cause, or when medical management has resolved the problem.

In the literature we searched we found no controlled studies of home methods for removing tonsil stones, so the tips below rest on general clinical practice and safety logic, not on trial evidence. Their aim is to limit the build-up of material in the crypts and to remove gently what is already visible, without injuring the tissue.

When stones are bothersome and keep returning despite conservative measures, an ENT doctor may propose a procedure. The two main options are cryptolysis (laser or other smoothing and closing of the crypts so that deposits cannot lodge in them) and tonsillectomy, the removal of the tonsils. The first has a smaller scope; the second solves the problem at its source but is a bigger operation.

The review by Ferguson et al. (2014), assessing the evidence on procedures for bad breath of tonsillar origin, states plainly that high-quality studies with control groups are lacking, while noting that where a procedure is justified and available, less invasive techniques such as laser cryptolysis may be preferable in adults to tonsillectomy, because they avoid general anaesthesia and the higher risk of complications. Note that these procedures are not the same as treating bad breath in general, and their effectiveness in studies depended on patient selection.

A whitish coating or spots on the tonsils can result from more than stones. In acute bacterial or viral tonsillitis they come with fever, severe sore throat and enlarged lymph nodes. White coatings in the mouth and throat can also be a sign of candidiasis, which we write about in the article on oral thrush in adults. When streptococcal tonsillitis is suspected, a diagnostic work-up is needed that a self-assessment of the throat's appearance cannot replace.

One-sided changes need particular attention. Enlargement of only one tonsil, an ulcer that does not heal, a hard lump or persistent asymmetry of the tonsils are reasons for ENT assessment, because they can point to a malignant process. A tonsil stone does not cause such changes, and their presence should not be explained away as stones without a medical examination.

Tonsil stones are one of those topics where much is said with certainty and little is known from studies. It is well documented that they are common and usually harmless; likely that in some people they worsen breath; uncertain which home and procedural methods work best. In practice a sensible order is: first oral hygiene and tongue scraping, then ENT assessment if symptoms persist, and a procedure only for persistent complaints.