What To Look For In A Dry Mouth Product

There is no best dry mouth product. That sounds like a cop-out and it is the most useful thing on this page, because it saves you paying a premium for an ingredient that has never been shown to beat a cheap one. A Cochrane review covering 36 trials and nearly 1,600 people found no strong evidence that any topical product reliably relieves dry mouth better than the others, and only one of those 36 trials was at low risk of bias.

What does change the answer is how much saliva you still make, when you need the help, how vulnerable your teeth are, and whether you can tolerate the thing enough to keep using it. Those are the criteria worth choosing on.

Start with the question nobody asks you

Does your mouth produce more saliva when something stimulates it? Chewing, tasting something, sucking a sweet.

If it does, you have working gland tissue, and stimulation is available to you. Sugar-free gum, lozenges and in some cases prescription medication all become worth trying.

If almost nothing happens, stimulation will disappoint you regardless of what you spend, and the effort belongs on coating and lubricating instead.

Most product guides skip this entirely, which is why so many people end up with a drawer full of things that did nothing.

The categories, and what each actually does

Substitutes and moisturisers add water, humectants and polymers to coat your mouth and reduce friction. They do not restore gland function and they do not reproduce saliva's buffering or antimicrobial properties. Best suited to severe dryness, overnight, or where stimulation isn't an option.

Taste stimulants use acid, flavour or sweetness to trigger the salivary reflex. Useful with mild to moderate reduction, generally before eating or speaking. Malic acid sprays have short-term evidence behind them from a small number of studies, and the acid is a real trade-off for your teeth.

Mechanical stimulants, meaning gum and things you suck, work through chewing rather than through anything in them. Flow rises while you chew. Cochrane found no evidence that gum relieves symptoms better than a substitute does.

Prescription stimulants, principally pilocarpine, act on the glands themselves. This is the only category with good evidence for increasing real saliva rather than adding moisture. It needs viable tissue and a prescription, and sweating limits it for a lot of people.

Dry mouth toothpastes clean and deliver fluoride, usually without the foaming agent and strong flavour of ordinary paste. Their defensible role is prevention. Nothing about them provides moisture between brushing.

Formats, and one myth worth killing

Gels last longer than sprays overnight. Everyone says it, including manufacturers, and there is no convincing independent trial showing it.

What is known is more modest. Where relief has actually been measured, it tends to run in minutes rather than hours. One crossover study in people with measured low saliva found a moisturising spray gave around 27 minutes of relief and plain water around 26, with no significant difference between them. Another trial of an experimental spray reported roughly an hour and a half against just over an hour for its comparator, with wide variation.

Gels should resist being cleared away better, on simple physical grounds. They may well suit you at night. But "up to eight hours" on a package is a claim about viscosity, not a measurement of relief through sleep.

Ingredients, and what the evidence actually shows

This is where most of the money goes and where the evidence is thinnest. Taking each in turn, with the negative findings included, because those are the ones nobody prints.

Cellulose-based thickeners are the workhorses of the category, used in most of the older prescribable products. They have been through more trials than anything else. Some of those trials were negative. Performance depends on concentration, pH and how quickly the product clears, not on the ingredient name.

Animal-derived mucin is the closest chemical mimic of what your own saliva contains, and small older studies reported benefit inconsistently. No durable superiority over cellulose was established. The mucin in Saliva Orthana is porcine, which matters if you are vegetarian, vegan, or observe halal or kosher requirements.

Xanthan gum thins under movement and thickens at rest, which is appealing in principle because that is how real saliva behaves. The clinical literature includes a xanthan-containing spray without clear symptom improvement. Laboratory behaviour has not translated into demonstrated duration.

Hyaluronic acid holds water well and adheres well. A 2023 crossover trial in 32 post-radiotherapy patients found better symptom scores and satisfaction than placebo. That is a real result from a small single-centre study, and it does not show hyaluronic acid beats inexpensive cellulose, which was never tested against it.

Polyethylene glycol was compared directly against Biotène in a 2026 crossover trial of 42 people. Both improved symptoms. The main analysis found no significant difference between them.

Carbomers make thick, adhesive gels and appear in several familiar products. No convincing trial demonstrates eight-hour relief or superiority over cellulose, and thickness can actually put people off using it.

Enzyme systems, using proteins such as lactoperoxidase and lysozyme, attempt to reproduce some of saliva's antimicrobial activity. There is no good evidence that adding them prevents thrush, decay or infection. They also introduce milk and sometimes egg-derived proteins, which matters for allergies and for anyone avoiding dairy.

Olive oil and betaine appear together in combination products. The evidence is for the whole formulation rather than for either ingredient, so neither can be credited. Natural does not mean it stays put.

Trehalose has one thesis-level study in post-radiotherapy patients reporting better quality of life than a cellulose spray. Unreplicated and insufficient.

Aloe vera outperformed flavoured saline in 60 people with diabetes, in a multi-ingredient spray, so the aloe cannot be identified as the active part.

Xylitol is a non-fermentable sweetener that doesn't feed the bacteria causing decay, and sucking or chewing something containing it can stimulate residual saliva. The small amounts present in sprays and gels are not an established decay-prevention dose.

Fluoride, calcium and phosphate in a product support your teeth rather than your comfort. Worth having, and no substitute for fluoride toothpaste.

The conclusion the evidence supports: no polymer class has won. Anyone marketing one as breakthrough technology is ahead of the data.

What actually matters: pH

This is the criterion almost nobody applies and it is the one with the most concrete evidence behind it.

Enamel dissolves below around pH 5.5, and dentine and exposed root surface at a higher pH, roughly 6.2 to 6.7. Both are working values rather than physical constants, since calcium, phosphate and fluoride levels shift them.

When your saliva is low, you have lost the buffering that would normally neutralise acid within minutes. So an acidic product used several times a day sits on your teeth in conditions where nothing is correcting it.

Published measurements of actual products, mostly from older testing, show a real spread:

That acidic result is the most concrete negative finding in this whole category, and it concerned a product that was routinely prescribed at the time. If you have your own teeth and you are using something several times a day, asking your dentist or pharmacist what its pH is now is a reasonable question. Formulations do change, so current figures may differ from anything published years ago.

Two caveats. These figures come from older studies and formulations get reformulated, so current values may differ. And a neutral pH on the bottle does not tell you everything, since how much acid a product contains and whether it is saturated with minerals also matter.

Alcohol and SLS: less clear-cut than you are told

Both get used heavily as marketing differentiators and the evidence is softer than the marketing suggests.

Alcohol. The claim that alcohol-containing mouthwash causes dry mouth is weaker than commonly stated. A 12-week randomised study in adults with normal saliva found no significant difference in flow or perceived dryness between alcohol-containing and alcohol-free rinses, though those were not people with dry mouth. A 60-day study found slightly more discomfort with alcohol rinses without clinically important tissue damage.

So the honest position is tolerability rather than causation. If your mouth is sore or irradiated, alcohol will sting and alcohol-free is the sensible choice. That is a different claim from alcohol drying you out.

Sodium lauryl sulphate, the foaming agent in most toothpaste. The evidence against it is about mouth ulcers rather than dryness. A review of four crossover trials in people with recurrent ulcers favoured SLS-free paste, while a 90-person trial found no difference in how many ulcers people got, though pain and duration improved.

Reasonable to choose SLS-free if your mouth is sore or you get ulcers. The idea that SLS causes dry mouth is largely convention.

Sugar, acid and flavour

Avoid sugary sweets for frequent use, which is obvious but gets forgotten with lozenges marketed for dry mouth.

Citric and malic acid do stimulate saliva where the glands still respond, and repeatedly exposing vulnerable teeth to acid is a poor exchange. Neutral, sugar-free mechanical stimulation is the safer default when your decay risk is high.

Strong mint, menthol and cinnamon can burn a sore mouth. That is tolerability rather than trial evidence, and it is a common reason people abandon a product.

Who should choose differently

After radiotherapy: if the damage is profound, neutral lubricants and sustained delivery beat stimulation. Fluoride is the priority, and repeatedly acidic products are the thing to avoid.

Sjögren's: residual secretion may respond to gum, lozenges or pilocarpine. No substitute is proven best, so choose on tolerability and pH.

Denture wearers: gel can be placed selectively under a well-fitting denture, though too much destabilises it. Rule out thrush and poor fit before blaming the dryness.

Very low residual function: skip the stimulants. Repeated lubrication, overnight coverage, fluoride and softer food textures are where the benefit is.

High decay risk: neutral and sugar-free, avoid frequent acid stimulation, and check the pH of anything you use several times daily.

Vegan, vegetarian, halal or kosher: avoid the porcine mucin products unless acceptable to you.

Milk or egg allergy: check enzyme-containing products carefully, since several use milk-derived proteins.

What is available in the UK

Prescription status changes, so confirm current availability rather than relying on any list including this one.

Disclosure, since it would be dishonest not to: ELVA is made by the dentist who wrote this page. It appears here on the same terms as everything else, including the absence of independent evidence behind it. If a product on this list has been independently tested and yours hasn't, that is a point in its favour, and you should weigh it accordingly.

Prescription or purchase?

Several products have historically been available on prescription, including Biotène gel, BioXtra gel and spray, Oralieve gel, Saliveze and Glandosane. Check the current position rather than assuming, since listings change.

Buying yourself, one pack a month works out somewhere around £80 to £120 a year for many gels, sprays and rinses. Severe users go through considerably more than that.

In England, dry mouth and Sjögren's are not on the medical exemption list for prescription charges. People being treated for cancer or its effects may qualify for exemption covering all prescriptions. If you pay for several items, a prepayment certificate may work out cheaper. And if you are paying the charge anyway, a prescription can cost more than simply buying an inexpensive product over the counter.

Claims to discount

• "Lasts up to eight hours." Usually based on thickness or selected user reports rather than independent comparison.
• "Clinically proven." Often one small short study against water or saline, not against a competitor.
• "Replaces natural saliva." Replaces moisture. Not buffering, not the protective film, not the antimicrobial proteins.
• "Restores natural defences." A plausible story with inadequate evidence that it prevents thrush, decay or infection.
• "Advanced polymer technology." No polymer class has been shown superior.
• "Contains xylitol, so prevents decay." Depends entirely on dose and frequency. Sweetener-level amounts are not a prevention regime.
• "pH neutral." Meaningful only if the finished product has been measured, which is rare.
• "SLS-free treats dry mouth." Better evidence for ulcer discomfort than for dryness.

How to choose, in order

Work out whether you have residual function, because it determines whether stimulation is worth anything. Decide when you need help most, since daytime and overnight suit different formats. Check the pH and sugar content if you have your own teeth and your decay risk is high. Check for animal-derived or milk proteins if that matters to you. Then try something, and switch if you can't stand it, because the best product is the one you are still using in three weeks.

Whatever you choose, it sits alongside fluoride rather than replacing it. No product on this list protects your teeth. That part is done by toothpaste, by how often you eat sugar, and by seeing a dentist more regularly than you otherwise would.

Sources

1. Furness et al. Interventions for the management of dry mouth: topical therapies. Cochrane, 2011.
2. MASCC/ISOO/ASCO. Management of salivary gland hypofunction and xerostomia. 2021, and clinical practice statement 2024.
3. Mercadante et al. Randomised crossover trial of hyaluronic acid in post-radiotherapy xerostomia. 2023.
4. Schwartz et al. Open-label crossover trial of a PEG-derivative rinse versus Biotène. 2026.
5. Kerr et al. Randomised crossover trial of a mucoadhesive disc. 2010.
6. Meyer-Lueckel et al. Effects of artificial saliva on enamel and dentine demineralisation. 2001. Note that formulations may have changed since.
7. Tanasiewicz et al. Crossover comparison of moisturising spray and water spray. 2021.
8. Jose et al. Duration of action of an aqueous dry mouth spray. 2016.
9. Kerr et al. Randomised study of alcohol-containing versus alcohol-free mouthrinse. 2015.
10. Vlachojannis et al. Clinical and cytological effects of alcohol mouthrinse. 2021.
11. Alli et al. Systematic review of SLS-free toothpaste in recurrent aphthous stomatitis. 2019.
12. Shim et al. Crossover trial of SLS-free dentifrice. 2012.
13. da Mata et al. Malic acid spray in xerostomia: systematic review. 2022.
14. Lopez-Pintor et al. Aloe vera spray in patients with diabetes. 2020.
15. BNF. Dry mouth treatment summary.
16. NHS Specialist Pharmacy Service, 2025, and NHS Drug Tariff, September 2026.
17. NHSBSA. Medical exemption certificates.

About this article. Written by Dr Jimmy Matloob, dentist. Published 20 September 2026. Last reviewed 20 September 2026.

This is general information about dry mouth. It is not advice about your individual situation, and it is not a substitute for being seen. If something here sounds like you, raise it with your dentist, doctor or pharmacist.

ELVA makes an alcohol-free dry mouth spray.