Sensitive toothpaste at Boots and Superdrug: reading the shelf by active ingredient.

The sensitive toothpaste shelf at Boots sorts into four families the moment you read the ingredient list instead of the front of the pack: a potassium salt for the nerve, a tubule-blocker (stannous fluoride, bioactive glass or arginine), hydroxyapatite, or nothing that treats dentine sensitivity at all. This page places every one of the twenty-seven Boots listings, and Superdrug's own label, in its family, with the level, the fluoride and the base as each pack publishes them in September 2026, and it says plainly where a level is not published. One list in the review carries potassium nitrate, hydroxyapatite and fluoride together, S3's, and it is sold direct rather than on either shelf (category review).

What was checked19 peer-reviewed studies, S3 consumer trial (ADSL, 2026), product information as published by each brand and retailer, the Oral Health Foundation and the NHS

How do you read a sensitive toothpaste pack in the aisle?

Turn the pack over and look for one of eight words in the ingredient list, because the front tells you the brand's shelf position and the list tells you the mechanism. Potassium nitrate, potassium citrate or potassium chloride mean a nerve-calming salt. Stannous fluoride, calcium sodium phosphosilicate (a bioactive glass, sold as NovaMin) and arginine mean a tubule-blocker. Hydroxyapatite, sometimes with "nano" in brackets, means the tooth's own mineral delivered as particles, which plugs tubules and settles on the surface. If none of those words appears, the pack is positioned for sore gums, worn enamel or gentle cleaning, whatever the word "sensitive" on the front is doing. The Journal's page on how sensitive toothpastes work explains what each active does once it reaches the tooth, and its page on what dentine tubules are explains why plugging them matters.

That is the whole method, in four moves:

• First, find the active among the eight words and note whether the list gives a percentage for it; on this shelf most lists do not.
• Second, find the fluoride line, which reads "Contains sodium fluoride 0.315% w/w (1450 ppm fluoride)" on the Sensodyne packs, "total fluoride content 1450 ppm" on the Colgate ones, and on both Oral-B packs appears only in the hazards text. A pack that names no fluoride salt anywhere is a fluoride-free paste.
• Third, look at the first two ingredients: "aqua" near the top means a water base, glycerin or PEG first with no water anywhere means an anhydrous base, and the base decides which actives the tube can hold.
• Fourth, read the price per 100 ml on the shelf-edge label rather than the tube price, because this shelf runs from a 20 ml serum to a 100 ml own-label tube.

Who is this shelf for, and why is it so crowded?

For a great many people, and most of them choose alone. In a cross-sectional survey of 3,551 adults across seven European countries, funded by Haleon, examiners recorded some response to a cold-air stimulus in 75.9% of participants, with the figure climbing through young adulthood and falling after the late thirties³. The companion paper on the same cohort, also funded by Haleon, found 29.1% had at least one tooth with a moderate or severe response, most often a lower front tooth on its cheek-facing surface, and that people with confirmed sensitivity were more likely to be using a desensitising toothpaste already⁴. The pooled picture is lower and wider: a 2019 systematic review of 77 cross-sectional studies put the best estimate at 11.5% of people and the plain average across surveys at 33.5%, which is where "up to one in three adults" comes from⁵. Whichever figure fits the UK, the shelf is crowded because the buyer is unsupervised. In a small industry-funded qualitative study of 18 adults with confirmed sensitivity, 16 of the 18 were using a desensitising toothpaste, every one had chosen it without a dentist's prompting, and none had been screened for the condition⁶. That is the reader of this page: phone in hand, no diagnosis, a wall of packs that all say "sensitive".

Which pastes on the Boots shelf carry a potassium salt?

Eight of the twenty-seven Boots listings, plus Superdrug's own label, and they run from the cheapest tube on the shelf to one of the dearest. Potassium nitrate is the salt in eight of the nine; the ninth, Spotlight Sensitivity + Rebuilding Pro, uses potassium citrate and also carries hydroxyapatite, so it appears again in the hydroxyapatite table. One of the nine declares the level of its potassium salt: Sensodyne's enamel-care paste states 5% w/w potassium nitrate, and the other eight publish a fluoride figure and nothing for the potassium. 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. Prices are as shown online on 2026-09-09, and the per-100 ml figures are arithmetic from the pack size shown.

The own label and Sensodyne's basic potassium paste publish the same two facts, potassium nitrate present and sodium fluoride at 1450 ppm, and neither tells you how much potassium is in the tube. What no pack on this shelf can tell you is how one unlabelled potassium paste compares with another once it is in a mouth; the evidence for the family, which is real but modest at two weeks, is in the evidence table below.

Which carry a tubule-blocking active, and which kind?

Eleven listings, in three chemistries, and the base is the tell. Six carry stannous fluoride, four carry a bioactive glass and one carries arginine; three of the stannous pastes and one of the glass pastes declare the level of their active, which makes this the best-labelled family on the shelf. The stannous pastes split by base: the two Oral-B pastes and Colgate's gum paste are water-based, while Sensodyne's stannous pastes and Corsodyl's are built on glycerin and PEG with no water, and both Oral-B listings declare their fluoride only in the hazards text, as 1100 ppm from stannous fluoride plus 350 ppm from sodium fluoride. The bioactive-glass pastes are water-free, or nearly so, because the glass reacts with water in the tube; the arginine paste is water-based and declares 8% arginine, the highest declared level of any active on the shelf. One listing is placed by its list rather than its description: Colgate's enamel-repair variant is described on the Boots page as a Pro-Argin paste, but its published ingredient list carries no arginine, so it sits in the last table.

What none of these eleven does is calm the nerve. Plugging a tubule and quietening a nerve are different jobs, hydroxyapatite does the first and potassium the second, and a formula built for sensitivity wants both.

Where does hydroxyapatite sit, and what does it cost you in fluoride?

At the top of the price range, and in three of the four Boots listings, without fluoride. Two Bioniq pastes and a Hismile serum list hydroxyapatite, the serum's as nano, and no fluoride salt at all, and none of the three publishes the hydroxyapatite level; Spotlight's paste keeps sodium fluoride at 1450 ppm beside hydroxyapatite and potassium citrate, with no level for either active.

The evidence for the family is stronger than its labelling. A 2023 systematic review and meta-analysis of 44 clinical trials, by authors who include a manufacturer's scientists, put the family's reduction in dentine hypersensitivity at 39.5% against placebo, and 23% beyond what fluoride toothpastes achieved; it pooled every form and format of hydroxyapatite together, so the figure belongs to the family and not to any one paste⁷. The 2026 network meta-analysis placed nano-hydroxyapatite among the most effective classes on the cold-air score at two weeks, a large effect with moderate confidence from two trials, even though its authors' headline named stannous fluoride and arginine as first line². The trial that the fluoride-free pastes lean on enrolled 105 adults in a double-blind randomised design: a fluoride-free 15% nano-hydroxyapatite paste beat both a fluoride paste and a placebo on the cold-air and tactile tests at two and four weeks⁸.

Where does S3 sit on this shelf?

Off the shelf and beside it: S3 is sold direct, not at Boots or Superdrug, and its list is the one in the review that pairs potassium nitrate with hydroxyapatite and keeps fluoride. What the Vano study left out is decay, and decay is the trade⁸. The NHS's own advice for keeping teeth free of toothache is to brush twice a day with a fluoride toothpaste, and a paste with no fluoride salt in its list has opted out of that⁹. Unlike fluoride-free hydroxyapatite pastes, S3 does not ask you to give up decay protection. Among 51 sensitivity toothpastes on sale in the UK in September 2026, S3 is the only one whose ingredient list carries potassium nitrate, hydroxyapatite and a fluoride salt together; the closest on the Boots shelf is Spotlight's paste, whose potassium salt is citrate, not nitrate. Every one of the 51 lists, with its source and the date it was read, is on the category review page, so that sentence can be checked rather than taken on trust. Superdrug's own label, read for this page, is a potassium nitrate and sodium fluoride paste and does not alter that. On the level column, one caution about S3's own numbers: 10% nano-hydroxyapatite and 5% biomimetic hydroxyapatite are inclusion levels of the ingredient as supplied, the active hydroxyapatite content is lower, and S3 states both.

Which "sensitive" pastes carry no desensitising active at all?

Five of the twenty-seven, and they are not hiding it: read the list and none of the eight words is there. Two are built on calcium carbonate with a zinc salt, one is a bicarbonate paste, one is an enamel-erosion paste whose calcium silicate and phosphate are meant to lay down new mineral rather than plug a tubule, and one is a gum paste with hyaluronate. Their own words place them. Arm & Hammer describes its paste as helping to protect exposed nerves, Euthymol describes care "without the intensity of the original formula", Marvis describes a paste "specifically designed to relieve sensitive gums", Regenerate describes enamel erosion and its reversal, and Colgate describes a Pro-Argin technology that the published list for that variant does not show. On fluoride, two of the five publish no figure anywhere on their Boots page, and the bicarbonate paste carries 1100 ppm where the rest of the shelf carries 1450 ppm.

None of this is a judgement on the pastes; a gum paste for sore gums is a reasonable buy. It is a judgement on the word "sensitive" on a shelf label, which covers gums, enamel, gentle cleaning and dentine hypersensitivity alike, and only the list tells you which one you are holding.

What does the evidence say for each family, and at what time point?

More than the packs say and less than the adverts. The anchor is the 2026 systematic review and network meta-analysis of 93 randomised trials in 9,548 adults, which compared each family with a plain fluoride toothpaste at two weeks and graded its confidence in every result². On the cold-air score, stannous fluoride gave a large reduction with high confidence, arginine a large reduction with low confidence, nano-hydroxyapatite a large reduction with moderate confidence from two trials, potassium a small but important reduction with low confidence, and bioactive glass a small reduction with low confidence². Its authors put stannous fluoride and arginine first for home use and said the choice between them should follow preference, tolerability and availability rather than any expectation that one outdoes the other². The same Bristol group's 2023 network meta-analysis of 32 randomised trials and 4,638 participants, whose authors declare manufacturer fees and grants, had already concluded that stannous, potassium with or without stannous, and arginine pastes can be recommended¹⁰.

Three older pooled analyses fill in what a two-week network leaves out. A 2015 meta-analysis of 31 randomised trials found potassium, stannous fluoride, bioactive glass and arginine pastes all reduced sensitivity versus placebo, with wide intervals and high heterogeneity, and found no significant effect for strontium, which no longer appears on this shelf¹¹. For potassium, the 2006 Cochrane review of six randomised trials measured its effect at six to eight weeks, found it on the air-blast and tactile tests but not in the patients' own ratings, and ended by calling the evidence unclear¹². The 2020 network meta-analysis of 125 randomised trials in 12,541 patients ranked bioactive glass highest across tactile, cold and air stimuli against fluoride toothpaste, and found large effects with moderate certainty for potassium combined with hydroxyapatite on tactile and air stimuli, the one pooled result that speaks to the pairing S3 uses¹³.

On timing, two manufacturer-funded trials are the most detailed on the shelf's two biggest families. In Procter & Gamble's own double-blind randomised trial of 120 adults, funded by the manufacturer, potassium nitrate, stannous fluoride and oxalate pastes all beat a plain fluoride paste on the cold-air test from day three, stannous fluoride beat potassium nitrate at week two and across the eight weeks, and three weeks after everyone switched back to the plain paste all three groups kept a benefit that was smaller but still significant¹⁴. In a manufacturer-funded randomised trial of 215 adults, run by Haleon as the maker of the paste, an anhydrous 5% bioactive-glass paste reduced sensitivity more than a plain fluoride paste from day three, and the gap kept widening to week eight¹⁵. The manufacturer-archive meta-analysis of 14 stannous fluoride trials with 1,287 participants, by Procter & Gamble authors, found a 22% advantage on the cold-air score over potassium nitrate or arginine pastes across six studies¹⁶. Between the two tubule-blocking chemistries, a 2019 systematic review and meta-analysis of five studies found no significant difference between arginine and bioactive-glass pastes at up to four weeks, with very low certainty¹⁷.

Potassium citrate, the salt in Spotlight's paste, has thinner evidence than potassium nitrate. The most recent citrate toothpaste trial found is a double-blind randomised trial of 56 adults from 2005 that compared two citrate pastes with each other and had no placebo arm¹⁸. The 2026 network review counted a single placebo-controlled citrate trial, at high risk of bias, and did not pool it².

Under the microscope, the mechanisms match the families. In a double-blind randomised trial of 30 adults with a companion SEM test, a 5% potassium nitrate paste reduced air-blast and cold-water sensitivity at four weeks, and the microscope arm found the tubules still open after the potassium paste¹⁹. In an in vitro SEM study on dentine discs, a 15% nano-hydroxyapatite paste occluded about 98% of tubules after seven days, against about 83% for a bioactive-glass paste and 69% for an arginine paste²⁰.

MD is the mean difference on the Schiff cold-air score or the Yeaple tactile score against a plain fluoride toothpaste in the 2026 network; SMD is the standardised mean difference against placebo in the 2015 review; confidence is the reviewers' own grading, not this page's.

Why does one brand appear in three families, and what does the base tell you?

Because a brand is a shelf position and an active is a mechanism, and the biggest brands cover every mechanism under sub-names. Sensodyne appears on this shelf with three potassium pastes, three bioactive-glass pastes and two stannous pastes. Colgate appears with three potassium pastes, a stannous paste, an arginine paste and one paste with no active in its list. Two people "on the same brand" can therefore be on different mechanisms, and a person who says a brand "stopped working" may have changed variant without noticing; the Journal's page on why a sensitivity toothpaste might not be working for you starts there.

The water column explains the chemistry. Bioactive glass reacts with water, so every glass paste on the shelf is built on glycerin and PEG; potassium nitrate dissolves in water, so the potassium pastes are water-based, with one exception built on glycerin and propylene glycol around hydrogen peroxide. Because S3 is built on water it can hold potassium nitrate and hydroxyapatite in the same tube, which a water-free formula built around bioactive glass cannot do. The fluoride salt follows the base too: S3 keeps 1450 ppm fluoride as sodium monofluorophosphate, chosen because it does not react with the calcium in hydroxyapatite inside the tube, and three of the four calcium carbonate pastes on the shelf use monofluorophosphate for the same reason. For decay protection the two salts came out equal in the one large head-to-head, a three-year double-blind randomised trial in 2,222 children²¹.

What about Superdrug and the supermarkets?

Superdrug's own label was read for this page in a browser on 2026-09-09, and it is the same family as the Boots own label: potassium nitrate and sodium fluoride in a water base, with no level for the potassium and no fluoride figure anywhere on the page, at £2.00 for 75 ml with a £1.00 member price shown. That is one product, not a shelf. Superdrug's category pages did not load, so the rest of its sensitive range is not described here, and the supermarket own labels were not read for this page: their sites refused the automated readers used for the September review, and no browser read of them was attempted here. This page therefore does not describe the supermarket own labels and does not guess. The method is the deliverable for those: turn the pack over, and if the list carries potassium nitrate and sodium fluoride with no percentage for the potassium, you are holding the same family, and you know exactly as much as the Boots or Superdrug buyer knows.

What should you do once you have read the shelf, and when should you skip it?

Choose a family for a reason, then give it the time the trials used. The Oral Health Foundation names potassium citrate, potassium nitrate and stannous fluoride as the ingredients to look for, says these pastes work by blocking the tiny channels in dentine, and says you have to keep using them to keep the effect¹. Its routine is the one printed on most of the packs above: brush twice a day, spit and do not rinse, use a soft brush with small circular strokes, and wait an hour after anything acidic before brushing¹. Judge a paste at the time point its evidence uses, which is day three to two weeks for the tubule-blockers in the trials above and six to eight weeks for potassium in the Cochrane review; S3 is judged at two to four weeks and is designed for twice-daily use as a complete toothpaste rather than a short treatment. A sensitive tooth usually has two things wrong at the same time, an over-ready nerve and open tubules, and most of the pastes on this shelf address one of them.

Skip the shelf when the pain is severe, has lasted more than a few weeks, sits in one tooth or came on suddenly, because the Foundation lists those as possible signs of decay, a cracked tooth, gum problems or infection¹. The NHS puts a shorter clock on plain toothache: more than two days is a dentist's job, not a GP's, and swelling that reaches the eye or neck is an emergency⁹.

Frequently asked questions

Is the Boots own-label sensitive toothpaste the same family as the branded ones?

Yes. Its published list is potassium nitrate with sodium fluoride at 1450 ppm in a water base, which is the family of six branded pastes in the first table and of Superdrug's own label, and like them it declares no level for the potassium. What you cannot tell from any of those packs is how much potassium nitrate each tube holds, because a single potassium paste on the shelf prints its percentage. Whether two pastes with the same two facts on the list behave the same in a mouth is a question no ingredient list answers.

Which family should I start with?

The one that matches what is wrong, which is why a dentist's view is worth having before the shelf. The 2026 network review's authors put stannous fluoride and arginine first for a paste used at home, chosen by preference and availability, and rated nano-hydroxyapatite's two-week effect large with moderate confidence and potassium's small with low confidence². For sensitivity from gum recession, where exposed tubules and a reactive nerve are both in play, a formula that carries a potassium salt and an occluder together covers both.

Why do some packs list glycerin first and no water?

Because the active needs a dry tube. Bioactive glass reacts with water, so every glass paste on the shelf is built on glycerin and PEG with no water in the list, and three of the stannous pastes and the peroxide whitening paste use the same kind of base. A dry base is neither better nor worse in itself; it decides which actives can share the tube, which is why you will not find potassium nitrate beside a bioactive glass, and why a paste built to hold potassium nitrate with hydroxyapatite has to be water-based.

Does a higher price mean a higher level of active?

No, and the shelf shows it both ways. The dearest tube in the potassium family is the one built around hydrogen peroxide, which declares no potassium level, while the one potassium paste that prints its level sits in the middle of the range; in the tubule family the arginine paste at £8.00 declares 8% and the £2.50 stannous paste declares nothing beyond its fluoride. Price buys a second mechanism, a declared level, a brand or a whitening agent, and only the list tells you which. The Journal keeps a ranked list of sensitivity toothpastes; this page is deliberately not one, and the cost-per-day arithmetic lives in the sibling guide on whether an expensive sensitivity toothpaste is worth it.

Is a fluoride-free hydroxyapatite paste a problem, and does S3 keep fluoride?

It is a trade, and you should make it knowingly. The three fluoride-free listings on the Boots shelf carry hydroxyapatite and no fluoride salt. They drop the decay protection that the NHS attaches to brushing with a fluoride toothpaste⁹. The evidence that hydroxyapatite itself reduces sensitivity is reasonable: a large effect with moderate confidence at two weeks in the 2026 network, from two trials². In a 105-adult double-blind randomised trial, a fluoride-free 15% nano-hydroxyapatite paste beat fluoride and placebo at two and four weeks⁸. S3 keeps full adult-strength fluoride, 1450 ppm as sodium monofluorophosphate, beside its two hydroxyapatites, and is SLS-free and vegan for the reader who checks that line too.