What are the spots on the back of my tongue?

Many people first notice the back of their tongue when they stick it out to look for a sore throat, and are alarmed by what they see. Several normal structures live there:

• Circumvallate papillae: a row of large, round, flat-topped bumps arranged in a V just in front of where the tongue curves down into the throat. Cleveland Clinic describes them as larger than the other papillae, each holding about 250 taste buds. They can look like pale or pinkish spots ringed by a groove.
• Foliate papillae: ridged folds on each side toward the back, which can look red or swollen when irritated.
• Lingual tonsil: lumpy lymphoid tissue covering the base of the tongue behind the V. It is part of the immune system, like the tonsils you can see at the sides of the throat, and can swell with colds.

These are symmetrical and have usually been there all along. Seeing them for the first time is not the same as them being new.

The back of the tongue is where coating builds up most. It moves less against the roof of the mouth than the front, saliva flow is lower there, and most people never brush it because it triggers the gag reflex. Bacteria, dead cells and post-nasal mucus settle between the papillae and form a white, yellow or gray film.

Common reasons it gets thicker:

• Dry mouth, mouth breathing or snoring
• Smoking and alcohol
• Colds, sinus infections and post-nasal drip
• Not cleaning the tongue at all

Coating on the back of the tongue is linked with bad breath, because the bacteria in it produce sulfur compounds. A coating that wipes off to show normal pink tongue underneath is not a disease. White patches that do not wipe off, or that wipe off to leave red raw spots, are different and are covered below. Our guides on thick white coating and white coating on the tongue go into more detail.

• Infection: tonsillitis, strep throat and colds can make the lingual tonsil and nearby papillae red and swollen, often with a sore throat and fever. Scarlet fever adds a rough rash and a strawberry-like tongue.
• Thrush: creamy white patches that wipe off to leave red areas, more likely after antibiotics, with asthma inhalers, dentures, diabetes or a weakened immune system.
• Inflamed papillae: irritated circumvallate or foliate papillae can look red and feel sore after spicy or acidic food, and settle in a few days.
• Cancer at the base of the tongue: uncommon, but important. The American Cancer Society notes that HPV, mainly type 16, causes most oropharyngeal cancers, the group that includes the base of the tongue, and these are increasingly seen in younger people. The NHS lists warning signs of mouth and throat cancers as an ulcer that lasts more than 3 weeks, a red or white patch, a lump in the mouth or neck, pain that does not go away and difficulty swallowing or speaking.

1. Stick your tongue out as far as it comfortably goes and breathe slowly through your nose; this reduces gagging.
2. Place the scraper as far back as you can without triggering a gag, then pull it forward with light pressure.
3. Rinse the scraper and repeat two to four times, covering the left, middle and right.
4. Stop if anything feels sore. You are removing a film, not scrubbing the tissue.

Evidence on tongue cleaning is modest but consistent in direction: a 2019 Cochrane review of halitosis treatments found that mechanical tongue cleaning slightly reduced breath odor scores, although the evidence was very low certainty. If you gag easily, see our tips on tongue scraping without gagging.

The NHS advises seeing a GP or dentist for a mouth ulcer lasting more than 3 weeks, a red or white patch, a lump, pain that does not go away, or difficulty swallowing. Because the back of the tongue is hard to see yourself, a dentist or ENT doctor can examine it properly with a mirror or scope if symptoms persist.