Chlorhexidine for Dogs UK: Products, Dilution Chart and Safety

Chlorhexidine is a topical antiseptic that reduces bacteria and yeast on a dog's skin — used as a 2–4% medicated shampoo, mousse, wipe or diluted rinse for pyoderma, hot spots, skin folds and yeasty paws. In the UK you will meet it as Malaseb (the prescription-only shampoo that pairs it with miconazole), Douxo S3 PYO (3%, sold without prescription), Hibiscrub (a 4% human skin cleanser some pet shops stock for dogs) and in a few ear cleaners and first-aid creams. What decides whether it works is not the brand but three details almost nobody publishes: the concentration you choose, how long it stays on the skin, and where you must never put it.

Stronger is not automatically better, and the ear canal is off-limits until a vet has checked the eardrum. This guide covers what chlorhexidine actually does, the chlorhexidine products sold in Britain and their legal status, the strengths veterinary research supports, a dilution chart in millilitres, realistic timelines — and the ceiling every owner eventually hits, where washing stops being the answer.

Quick answer for UK owners: for a confirmed yeast (Malassezia) skin infection, the best-evidenced wash is the 2% chlorhexidine + 2% miconazole shampoo — in the UK that is Malaseb, a POM-V medicine your vet prescribes. A 3% chlorhexidine shampoo on its own, such as Douxo S3 PYO, needs no prescription and has moderate evidence. Leave any medicated lather on for 10 minutes, bathe two to three times a week during a flare, keep it out of eyes and ears, and save 4% products for short, vet-directed courses.

What chlorhexidine is and how it works on a dog's skin

Chlorhexidine — usually labelled chlorhexidine gluconate, digluconate or acetate — is a broad-spectrum antiseptic, not an antibiotic in the traditional sense. The molecule carries a positive charge; microbial cell walls carry a negative one. Chlorhexidine binds to them, disrupts the membrane and kills the organism, which is why it works against a wide range of bacteria and yeast rather than one narrow target.

Its second property matters just as much: substantivity. Chlorhexidine binds to the outer skin layer and hair and keeps working after you rinse. Santoro's 2023 review of topical therapy for canine pyoderma reports a measurable residual effect on hair for 7 to 14 days after treatment — but on the skin itself, that inhibitory effect lasted only about 4 days. That gap explains a lot of owner frustration: the coat may still be "protected" while the skin is already vulnerable again.

The organisms it targets in dogs are mainly Staphylococcus pseudintermedius (the usual cause of superficial bacterial folliculitis, or pyoderma) and Malassezia pachydermatis, the yeast behind most cases of yeast dermatitis in dogs — the greasy, musty-smelling skin, brown-stained paws and itchy folds so familiar to owners of Westies, Basset Hounds, Cocker Spaniels and Shih Tzus.

Chlorhexidine products you'll find in the UK

British owners searching for "chlorhexidine for dogs" usually have one of a handful of bottles in mind. They are not interchangeable: the strength, the legal status and what each one is designed for differ a lot.

Do you need a prescription for chlorhexidine in the UK?

Mostly no. The Veterinary Medicines Directorate (VMD) sorts every authorised animal medicine into a legal category under the Veterinary Medicines Regulations 2013: POM-V (vet prescription), POM-VPS (vet, pharmacist or suitably qualified person), NFA-VPS and AVM-GSL (general sale). Chlorhexidine-only shampoos, mousses, wipes and cleaners are sold without a prescription. The exception that matters for yeast is Malaseb: because it contains the antifungal miconazole and is authorised to treat Malassezia dermatitis, it is POM-V, so your vet must examine your dog first.

You do not have to buy the prescribed shampoo at the practice. Ask for a written prescription and compare prices at online vet pharmacies on the VMD's Accredited Internet Retailer Scheme. Following the Competition and Markets Authority's final decision on the vet market (March 2026), the fee for a written prescription is being capped at £21 for the first medicine and £12.50 for each additional one — from March 2027 at large vet groups and September 2027 at smaller practices. For the bigger picture of what UK vets prescribe for yeast and what it costs, see our guide to dog yeast infection treatment in the UK.

What chlorhexidine is used for in dogs

Surgical scrubs sit in a separate category — high-concentration products meant for pre-operative skin preparation in a vet practice, not for repeated home use on inflamed skin.

Does chlorhexidine kill yeast on dogs?

Yes, and this is where the evidence is strongest. The World Association for Veterinary Dermatology's clinical consensus guidelines on Malassezia dermatitis — whose first author, Ross Bond, is at the Royal Veterinary College — grade the topical options explicitly, and only one earns their top grade: a shampoo combining 2% chlorhexidine with 2% miconazole, used twice weekly, carries "strong evidence." A 3% chlorhexidine shampoo on its own is graded "moderate evidence."

That grading comes from real trials. Bond and colleagues (1995) randomised 33 Basset Hounds with Malassezia-associated seborrhoeic dermatitis; every dog in the miconazole–chlorhexidine group improved, with significantly greater reductions in itching, redness, exudation and yeast counts than the comparison shampoo. A later randomised trial by Maynard and colleagues (2011) compared 3% chlorhexidine alone against the 2%/2% combination and found chlorhexidine alone held its own — roughly 88% or greater yeast-count reduction in nearly every compliant dog, with no statistically significant difference in lesion scores. Both papers appeared in the Journal of Small Animal Practice, the BSAVA's journal.

For UK owners that translates neatly: the 2%/2% combination is Malaseb (prescription), and a 3% chlorhexidine-only shampoo such as Douxo S3 PYO is the reasonable non-prescription alternative — for example between vet appointments, or as maintenance once your vet has brought a flare under control.

The reason the combination is favoured is synergy: laboratory work summarised in Santoro's review shows that pairing chlorhexidine with an azole substantially lowers the concentration needed to inhibit staph. For the azole side of that partnership, we cover miconazole for dogs and ketoconazole for dogs separately. Oral azoles are a different tool altogether: they reach yeast through the bloodstream, and in the UK vets often prescribe them for dogs under the VMD's prescribing cascade.

One honest caveat: chlorhexidine reduces yeast, it does not remove it for good. Malassezia is a normal resident of canine skin that overgrows when conditions favour it. Killing the surface population without changing those conditions buys weeks, not permanence.

2% or 4%? Why stronger is not safer

Plenty of product marketing treats 4% as the "vet strength" upgrade, and in the UK the most widely available 4% bottle is Hibiscrub. The research does not support that reflex.

A 2025 study in the Journal of Veterinary Medical Science applied 0.05%, 0.5% and 4% chlorhexidine gluconate daily to dogs' skin for two weeks and measured barrier function. The 4% concentration produced a notable rise in transepidermal water loss and a drop in skin surface hydration — in plain terms, it dried out and destabilised the skin barrier. The 0.5% concentration delivered adequate antimicrobial effect without that barrier disruption. A cell assay in the same work found cytotoxicity to canine skin cells at concentrations as low as 0.05%.

Formulation matters as much as percentage. Santoro's review noted that shampoos containing 2% and 3% chlorhexidine showed greater residual bacterial inhibition than some products with up to 4% — the base the chlorhexidine sits in changes how well it deposits and holds on the skin.

Practical read: if your dog's skin is already inflamed, raw or barrier-damaged, the lower concentrations are the safer starting point. Save 4% for a short, vet-directed course rather than an indefinite routine.

Chlorhexidine dilution chart for dogs (in millilitres)

This is the question veterinary sources answer inconsistently, so here is the arithmetic in one place, in UK measures. These figures apply to superficial skin rinses, paw soaks and fold cleaning only — never to deep, puncture, bite or surgical wounds, never to eyes or mucous membranes, and never to ears.

Mix fresh each time in a clean jug, use lukewarm water, and pour away what you don't use — a diluted solution sitting in a bottle is an unpreserved one. Use a medicine syringe or measuring jug marked in millilitres; the ratio column is the figure to trust. If you are working from a concentrated surgical scrub rather than a labelled 2% or 4% product, do not estimate. Ask your vet for the exact dilution, because the gap between a useful rinse and a barrier-damaging one is a factor of ten.

Wherever possible, a finished veterinary-labelled product used at its label concentration beats home dilution. The formulation has been designed to deposit and hold; a hand-mixed solution has not.

Contact time: the step that decides whether the bath worked

The ISCAID guidelines on canine superficial bacterial folliculitis are specific: contact time should be at least 10 minutes before rinsing, with baths commonly given two or three times weekly until 7 days after lesions resolve, then weekly for prevention. Douxo S3 PYO's own directions say 5 to 10 minutes; for an active problem, aim for the full 10. Keeping the coat short helps the product reach skin rather than sitting on hair.

Ten minutes with a wet, unhappy Spaniel is longer than it sounds, and cutting it short is the single most common reason a medicated bath underperforms. What helps:

• Rinse the mud off with plain water first — chlorhexidine works on clean skin, and a pre-rinse means the medicated lather isn't wasted lifting the dirt from a wet British walk.
• Lather, then set a timer. Do not guess.
• Work the lather into problem zones with your fingertips: between the toes, armpits, groin, under the tail and into facial and tail folds.
• Keep the dog warm — a bathroom with the door shut and the shower running warm holds the heat, which matters in an unheated utility room in January.
• Occupy them. A lick mat stuck to the side of the bath buys most of the ten minutes on its own.
• Rinse thoroughly. Residue left in the coat is a common cause of irritation being blamed on the product.
• Dry properly — towel, then a cool hairdryer setting if your dog tolerates it, paying attention to between the toes and inside folds.

Keep chlorhexidine well clear of the eyes; corneal injury after direct contact is a documented risk, and veterinary product labels say to avoid it. And don't let your dog lick or chew a treated area for at least 30 minutes after application.

Chlorhexidine and the British climate: paws, folds and wet walks

Yeast loves warmth and moisture, and the UK supplies the moisture generously: Met Office climate averages put most of the country at roughly 155–160 days a year with at least 1 mm of rain. Paws that come home wet twice a day, feathered Spaniel feet that stay damp for hours, and the skin folds of French Bulldogs, Pugs and Bulldogs are the classic UK hot spots for Malassezia.

• After walks: plain water and thorough drying between the toes do more for yeasty paws than chlorhexidine after every walk. Keep the 0.5% paw soak or a chlorhexidine wipe for flare-ups or a few times a week, not twice daily — the barrier data above is the reason.
• Skin folds: a chlorhexidine wipe once a day during a flare, then every other day, followed by drying the fold completely.
• Know what else itches: in late summer and autumn, harvest mites cause intense itching on paws, ears and bellies, and grass pollen (roughly May to July) drives allergic itch. Neither is a yeast problem, and chlorhexidine will not touch either — another reason to get a diagnosis before a bathing routine. Our guide to dog paw yeast infection walks through how to tell them apart.

The ear canal: where to stop

This is the hard line in this article. Do not put a chlorhexidine product into your dog's ear canal unless a vet has examined the eardrum and specifically recommended it.

Chlorhexidine is recognised as ototoxic. Professor George Strain, writing in the Journal of Small Animal Practice, noted that it has long been kept out of licensed ear medicines in the United States. Higher concentrations reaching the middle ear are reported in the veterinary literature to damage cochlear and vestibular structures, with permanent deafness or balance problems as possible outcomes.

The problem is that you cannot see an eardrum from the outside. A ruptured tympanic membrane is common in dogs with chronic ear disease and gives no obvious external sign — and ear disease is common in British dogs: Royal Veterinary College VetCompass data from UK first-opinion practices put the annual prevalence of otitis externa at 7.3%, with Basset Hounds among the highest-risk breeds. The Merck Veterinary Manual is direct on this point: if the eardrum is ruptured, detergents are contraindicated and milder flushes such as saline or Tris-EDTA should be used instead.

In the UK some over-the-counter ear cleaners do contain chlorhexidine — Otodine pairs it with Tris-EDTA — and its own instructions tell you to check for an intact eardrum before use. Others contain none at all. For routine cleaning of waxy, yeast-prone ears once your vet has confirmed the drum is intact, our Pure Majesty Pets Dog Ear Cleaner (£23, 120 mL) is chlorhexidine-free and pH-balanced at 5.0–5.5, with 0.2% salicylic acid to soften wax and 10% aloe to soothe — and, like every ear cleaner, it should not be used on a ruptured eardrum.

If your dog develops a head tilt, circling, flicking eye movements, sudden loss of balance or apparent deafness after any ear product, treat it as an emergency and call your vet or an out-of-hours service such as Vets Now. For the safe approach to yeasty ears, see our guide to dog ear yeast infection.

Side effects and safety

Dogs tolerate chlorhexidine well as a rule, which is exactly why it is easy to over-use. The reactions worth knowing:

• Skin irritation or redness at the application site — the most common complaint, more likely at higher concentrations or with frequent use.
• Dryness and barrier damage with repeated 4% use, per the 2025 barrier study.
• Slower wound healing if used repeatedly on open wounds.
• Corneal injury from eye contact.
• Delayed sensitivity. Sensitivities can develop with repeated exposure — a dog that was fine with it for months can start reacting.
• Allergic reaction — facial swelling, hives, irregular breathing or fever warrant an immediate call to your vet.
• Swallowing. A small lick usually causes no more than drooling or a mild stomach upset, but it is not meant to be swallowed. Wait 30 minutes, or use a buster collar. If your dog drinks a larger amount, call your vet; the Animal PoisonLine (01202 509000) also gives owners poisons advice.

Can I use Hibiscrub or Savlon on my dog?

Hibiscrub is the bottle most UK households already have, and it is the same 4% strength that the 2025 study linked to barrier damage with daily use. It is formulated as a skin cleanser for intact human skin. If your vet is happy for you to use it, dilute it to 0.5% (25 mL in 175 mL of water) for rinses and soaks, never use it neat on inflamed skin, and keep it away from eyes and ears.

Savlon Antiseptic Cream contains only 0.1% chlorhexidine plus cetrimide and is designed for people. On a dog it mainly gets licked off, and it is not a treatment for yeast or pyoderma. For a minor graze, clean with salt water or a dilute chlorhexidine rinse and ask your vet before reaching for human creams.

What to realistically expect, and when

The ceiling chlorhexidine can't cross

Here is what owners discover the expensive way. Chlorhexidine is a surface intervention. It reduces the microbial population sitting on the skin, and it does that well. What it cannot do is change why that population keeps coming back.

The WAVD guidelines are clear that Malassezia is a normal skin resident whose overgrowth follows something else — excess sebum, a disrupted skin barrier, allergic disease, cornification defects, or a hormonal disorder such as hypothyroidism or Cushing's. Dogs with Malassezia dermatitis frequently have a concurrent hypersensitivity disorder, and the West Highland White Terrier is the textbook UK example of an atopic, yeast-prone dog. So the bath knocks the yeast back, the underlying driver stays put, and four weeks later you are back in the bath. If that pattern sounds familiar, our guide to recurring yeast infection in dogs works through the causes worth investigating.

There is a second, less obvious cost. If the answer to every flare is a stronger, more frequent wash, the 2025 barrier data suggests you may be wearing down the very skin barrier your dog needs to resist the next overgrowth.

That is the case for supporting the skin from the inside, alongside — not instead of — vet-directed topical care. Our Pure Majesty Pets Yeast Support Drops are built on that logic: oral drops given with food, carrying roughly 292 mg of actives per millilitre across 19 named ingredients, working on three fronts at once.

• Yeast balance: caprylic acid from MCT C8 (45 mg), apple cider vinegar (18 mg), NAC (18 mg), berberine from Berberis aristata (15 mg), pau d'arco (8 mg) and oregano standardised to 70% carvacrol.
• Skin comfort and barrier: MSM (45 mg), wild salmon oil (35 mg), quercetin (15 mg), calendula (8 mg) and elemental zinc (2 mg).
• Gut–skin axis: L-glutamine (25 mg) and a Saccharomyces boulardii postbiotic (20 mg), with pumpkin, slippery elm, marshmallow root, DGL liquorice, aloe and ginger.

Two things we state plainly rather than blur. The S. boulardii here is a stabilised postbiotic cell-wall fraction, not a live-CFU probiotic, and we label it that way. And while medium-chain fatty acid esters have shown activity against Malassezia pachydermatis in laboratory work — including azole-resistant isolates (Koch et al., 2022) — that research is in vitro. Current research does not prove that any oral supplement reduces Malassezia counts on canine skin. What the evidence does support is that oral fatty acids and gut support belong in the management of the allergic, barrier-compromised skin that lets yeast take hold. Under UK feed law our drops are complementary feed: they support normal skin and gut function, and they sit alongside your vet's plan rather than replacing it.

When to call your vet instead of reaching for the shampoo

• Any ear involvement with pain, head tilt, imbalance or a suspected eardrum problem.
• Draining tracts, nodules, ulceration, fever or obvious pain — signs of deep pyoderma, which typically needs culture-guided oral antibiotics for 8 to 16 weeks.
• No improvement after 3–4 weeks of appropriate topical therapy.
• Infections that clear and return within weeks — that is an underlying-disease signal.
• Any facial swelling, hives, breathing changes or worsening redness after application.
• Puppies under 8 weeks, pregnant dogs, or dogs already on other medicated topicals.

Diagnosis matters more than product choice. Bacterial, yeast and mixed infections look alike to the eye and need different handling, and the reliable way to tell them apart is cytology — a tape strip or swab stained and read under a microscope. It is a quick in-practice test that stops you treating the wrong organism for a month. The RCVS Find a Vet directory lists practices near you, and if your dog is insured (Petplan, ManyPets and others), check how a recurring skin problem will be handled at renewal. Our guide to dog yeast infection shampoo compares the main washes your vet may suggest.

Frequently asked questions

Do I need a prescription for chlorhexidine for dogs in the UK?

Not for chlorhexidine-only shampoos, mousses, wipes and cleaners such as Douxo S3 PYO, which are sold without a prescription. Malaseb, which combines chlorhexidine with the antifungal miconazole, is a POM-V medicine and needs a vet's prescription. You can ask for a written prescription and buy it from an online vet pharmacy.

Can I use Hibiscrub on my dog?

Hibiscrub is a 4% chlorhexidine skin cleanser made for people, and some UK pet shops sell it for dogs. Used neat and often, 4% chlorhexidine can dry out and damage the skin barrier, so if your vet agrees, dilute it to about 0.5% (25 mL in 175 mL of water) for rinses and paw soaks, and keep it away from eyes and ears.

Can I use Savlon on my dog?

Savlon Antiseptic Cream contains 0.1% chlorhexidine with cetrimide and is designed for human skin. Dogs tend to lick creams off, and it is not a treatment for yeast or skin infections. Ask your vet before using human first-aid creams on your dog.

How often can I bathe my dog with chlorhexidine shampoo?

Veterinary guidelines commonly use two to three times weekly during an active infection, continuing for about 7 days past the point lesions clear, then dropping to weekly for maintenance. Daily use of a 4% product is where barrier problems appear.

Do you rinse chlorhexidine off or leave it on?

Shampoos are rinsed after about 10 minutes of contact. Sprays, mousses and wipes are leave-on products and should be allowed to dry.

Chlorhexidine or miconazole — which is better for yeast?

Together, according to the strongest evidence. The 2% chlorhexidine plus 2% miconazole combination (Malaseb in the UK) is the only topical protocol the WAVD guidelines grade as having strong evidence for Malassezia dermatitis. Chlorhexidine at 3% alone performs respectably and is a reasonable non-prescription option.

Is Leucillin the same as chlorhexidine?

No. Leucillin is a hypochlorous acid spray (HOCl in salt water), a different antiseptic altogether. It does not contain chlorhexidine, and the chlorhexidine evidence in this article does not apply to it.

Does chlorhexidine kill ringworm?

Chlorhexidine is less reliable against dermatophytes than against bacteria and Malassezia. Ringworm is a different organism and needs a specific antifungal plan from your vet, usually alongside cleaning the home environment.

Can I use chlorhexidine on my dog's paws?

A dilute chlorhexidine foot soak is a common approach for yeasty, stained, licked-at paws. Use the 0.5% dilution, soak for a few minutes, then dry thoroughly between the toes — trapped moisture from wet walks is half the problem.

What if my dog licks the treated area?

Small amounts usually cause nothing worse than drooling or a mild stomach upset. Keep your dog occupied for 30 minutes after application, or use a buster collar. Call your vet if a significant amount was swallowed or vomiting persists.

Does chlorhexidine shampoo dry out a dog's skin?

It can, particularly at 4% and with frequent use — that is precisely what the 2025 barrier study measured. A lower concentration, a conditioning formulation, or spacing baths further apart all help.

Can I use chlorhexidine shampoo alongside a medicated shampoo I already have?

Check with your vet before layering products. Two degreasing shampoos in the same week is a common route to irritation.

Scientific and UK references

1. Bond R, Morris DO, Guillot J, et al. Biology, diagnosis and treatment of Malassezia dermatitis in dogs and cats: Clinical Consensus Guidelines of the World Association for Veterinary Dermatology. Veterinary Dermatology. 2020;31(1):28-74.
2. Hillier A, Lloyd DH, Weese JS, et al. Guidelines for the diagnosis and antimicrobial therapy of canine superficial bacterial folliculitis (Antimicrobial Guidelines Working Group of the International Society for Companion Animal Infectious Diseases). Veterinary Dermatology. 2014;25(3):163-e43.
3. Negre A, Bensignor E, Guillot J. Evidence-based veterinary dermatology: a systematic review of interventions for Malassezia dermatitis in dogs. Veterinary Dermatology. 2009;20(1):1-12. PMID 19152584.
4. Bond R, Rose JF, Ellis JW, Lloyd DH. Comparison of two shampoos for treatment of Malassezia pachydermatis-associated seborrhoeic dermatitis in basset hounds. Journal of Small Animal Practice. 1995;36(3):99-104. PMID 7783442.
5. Maynard L, Rème CA, Viaud S. Comparison of two shampoos for the treatment of canine Malassezia dermatitis: a randomised controlled trial. Journal of Small Animal Practice. 2011;52(11):566-572. PMID 21985533.
6. Borio S, Colombo S, La Rosa G, et al. Effectiveness of a combined (4% chlorhexidine digluconate shampoo and solution) protocol in MRS and non-MRS canine superficial pyoderma: a randomized, blinded, antibiotic-controlled study. Veterinary Dermatology. 2015;26(5):339-e72. PMID 26140535.
7. Santoro D. Topical therapy for canine pyoderma: what is new? Journal of the American Veterinary Medical Association. 2023;261(S1):S140-S148. PMID 36921021.
8. Daily topical application of chlorhexidine gluconate to the skin in dogs and its impact on skin barriers and cytotoxicity. Journal of Veterinary Medical Science. 2025;87(3). PMID 39814393.
9. Strain GM. Chlorhexidine. Journal of Small Animal Practice. 2018;59(1):60. PMID 29193161.
10. Koch S, et al. Medium-chain fatty acid esters are effective even in azole-resistant Malassezia pachydermatis. Mycoses. 2022. DOI 10.1111/myc.13512. PMID 35923130.
11. O'Neill DG, et al. 2021. Royal Veterinary College VetCompass study of otitis externa in UK first-opinion practice (annual prevalence 7.3%).
12. Veterinary Medicines Directorate. The cascade: prescribing unauthorised medicines. GOV.UK.
13. Savlon Antiseptic Cream — Summary of Product Characteristics. electronic medicines compendium (eMC).
14. Competition and Markets Authority final decision on UK veterinary services (March 2026): prescription fee cap of £21 explained.
15. Met Office. UK climate averages 1991–2020 (days of rain ≥1 mm).

Veterinary disclaimer: This article is general information for UK dog owners and is not a substitute for veterinary diagnosis or treatment. Use chlorhexidine products according to their label and, where skin or ear disease is suspected, under the direction of your vet; POM-V medicines such as Malaseb must only be used as prescribed. Retail prices were checked on live UK pages in October 2026 and will change. Pure Majesty Pets supplements are complementary feed and are not intended to treat or prevent any disease. Talk to your vet before starting any supplement, particularly if your dog is on medication, pregnant or has a diagnosed condition.