UK sensitivity toothpastes by declared ingredient: the category review behind "only S3".

This page is the table behind one sentence: that S3 is the only sensitivity toothpaste on sale in the UK whose published ingredient list carries potassium nitrate, hydroxyapatite and a fluoride salt together (category review of 51 products, September 2026). It lists every sensitivity toothpaste the review could find on the UK shelf in September 2026, 51 with the ingredient list read from the brand's or a retailer's own page and nine that could not be read, grouped by the desensitising active the list actually contains, with the level declared, the fluoride, the base, the price as shown, the source and the date. Read it to check the sentence, or to place the tube in your hand in its family.

What was checked2 peer-reviewed studies, product information as published by each brand and retailer, the Oral Health Foundation

This page compares ingredients and stated actions only, not clinical performance, based on what each brand states about its own formula. Prices and formulations may change; always check the pack.

How was the shelf read?

From the pages the brands and retailers publish, and from nothing else. The review started with the Boots.com search for sensitive toothpaste and with brand-name searches on Boots, then fetched every brand's own UK site; where the brand publishes no ingredient list, as the Haleon and Procter & Gamble UK sites do not, the Boots product page is the source, and where a brand has no UK site, one UK retailer listing with the list in its text was saved beside the brand's page. Each page was saved once, dated, and never edited; the row points to it. Search-engine summaries, ingredient aggregators and review sites were never used as a source of an ingredient list, so a product whose list exists only there is marked pending, not recorded.

The columns are read, not typed. The actives, the fluoride salt, the presence of water and the combinations of actives are computed from the ingredient string by the build script; the level column is the brand's own declared concentration where the page states one and "no" where it does not; the price is the price shown on the day, with the pack size where the page gives one. A product with several actives appears in each of their tables, and the row id is the same in every table.

Which products carry potassium nitrate?

Eleven competitors and S3, and three of the twelve declare the level of the potassium. Potassium nitrate is the nerve-side active: the Oral Health Foundation lists it, with potassium citrate and stannous fluoride, among the ingredients to look for on a sensitivity pack¹. Every potassium nitrate list here also carries a fluoride salt, and all but one sit in a water base, because the salt dissolves in water.

six further products carry a different potassium salt, citrate or chloride, without the nitrate:

Which carry hydroxyapatite?

16 competitors and S3, in three forms of the mineral and two kinds of tube. Hydroxyapatite is the tooth's own mineral delivered as particles; the list may say hydroxyapatite, hydroxyapatite (nano) or zinc hydroxyapatite, and a brand may declare the form as nano or biomimetic on its page. The split that matters to a buyer is the fluoride column: 13 of these products carry no fluoride salt, and three competitors pair hydroxyapatite with a fluoride salt.

Which carry a tubule-blocker: stannous fluoride, a bioactive glass or arginine?

14 products, in three chemistries, and the best-labelled family on the shelf. Stannous fluoride is a fluoride salt that also blocks tubules; calcium sodium phosphosilicate is a bioactive glass sold as NovaMin, with calcium phosphosilicate and fluoro calcium phosphosilicate as its relatives; arginine with calcium carbonate is the Pro-Argin system. The glass reacts with water, so its pastes are built without any, and most of the stannous pastes here are too.

Which "sensitive" products carry none of those actives in their published list?

Eight recorded products, and the list is the only way to tell. They are positioned for sensitive gums, worn enamel or gentle cleaning, on calcium carbonate, bicarbonate, calcium silicate or a zinc salt; the word "sensitive" on the front covers all of those. This is not a judgement on the products, only a note that none of the eight ingredient words that mark a desensitising active appears in their lists.

Which combine two of the three actives, and which all three?

Two-of-three is ordinary; three-of-three occurs once. Of the 51 recorded lists, potassium nitrate with a fluoride salt appears in 11 competitor products, hydroxyapatite with a fluoride salt in 3, and potassium nitrate with hydroxyapatite in none; the one list that carries potassium nitrate, hydroxyapatite and a fluoride salt together is S3's, row CR-028. The nearest list is Spotlight Sensitivity + Rebuilding Pro, which pairs hydroxyapatite and sodium fluoride with potassium citrate, a different potassium salt with thinner trial evidence than the nitrate.

The pairing matters because the two actives do different jobs. The 2020 network meta-analysis of 125 randomised trials is the one pooled result that speaks to the pairing: potassium together with hydroxyapatite showed large effects against fluoride toothpaste on the tactile and the air stimulus at moderate certainty, and potassium alone was ranked for touch only². The 2026 network meta-analysis of 93 randomised trials graded each family against a plain fluoride paste at two weeks: high confidence for stannous fluoride, a large but two-trial result for nano-hydroxyapatite, and a small, low-confidence result for potassium³. Neither review is a verdict on any product in these tables; both are the reason the combination column exists.

The base explains the pattern. Bioactive glass needs a water-free tube and potassium nitrate dissolves in water, so the glass pastes and the potassium pastes live in different tubes; S3's water base is what lets potassium nitrate and hydroxyapatite share one. The Journal's page on how sensitive toothpastes work explains the two jobs from the other direction.

What could not be read, and what was not found?

Five products are pending and four were not found, and this page does not guess at either. Pending means a product exists on the UK market but its ingredient list could not be read from a permitted page on the day: the brand publishes no list in page text, or the retailer refuses automated readers, as Superdrug's category pages and the supermarket sites did. Not found means the review searched the Boots shelf and the brand's UK site and found no sensitivity variant on sale in the UK.

A row moves from pending to recorded when a permitted page with the list is read; the date on the row changes with it, and so does the count in the first paragraph.

How do you check a row yourself?

Open the source named in the row and read the ingredient list on it. Every recorded row carries the URL it was read from and the name of the saved copy, with the date it was read; the saved copy is the review's evidence and the live page is yours. If the live list differs from the row, the pack has been reformulated since the read, which is exactly what the pack-may-change line at the top of this page is for, and the row is due a re-read. The eight words that place a product in a family are potassium nitrate, potassium citrate, potassium chloride, stannous fluoride, calcium sodium phosphosilicate, arginine, hydroxyapatite and, for the last family, none of them.

Frequently asked questions

Does "only S3" mean S3 is the best sensitivity toothpaste?

No. It means one thing, which the tables show: among the 51 published ingredient lists the review could read, S3's is the only one with potassium nitrate, hydroxyapatite and a fluoride salt together. This page compares ingredients and stated actions only, not clinical performance, and the two reviews it cites rate families of actives, not products²³.

Why are some well-known products missing?

Because their list could not be read from a permitted page, or because no sensitivity variant was found on the UK shelf. Elmex, Aquafresh and Crest sensitivity pastes are sold elsewhere but were not found on sale in the UK; the Superdrug and supermarket own labels are pending because those sites refuse automated readers. A pending row is not a claim that the product lacks anything.

How current is the table?

Every row carries its read date and the saved copy of the page it came from. Formulations change without notice, so a row can be out of date the day after it is read; the pack in your hand is the authority, and this page tells you which eight words to look for on it.

What is a "family", and can a product be in two?

A family is the desensitising active the list contains: potassium nitrate, another potassium salt, hydroxyapatite, a tubule-blocker, or none of those. A list with two actives sits in two tables under the same row id; Spotlight's paste, for instance, appears under the other potassium salts and under hydroxyapatite.