Posted by Stephen Crowther
on April 30, 2026
Your dog is scratching, the skin is red, and there's something there that wasn't there yesterday. The three most common things UK vets see in this situation are hot spots, allergies, and bacterial or yeast infections — and they look frustratingly similar at first glance. The treatment for each is different, and getting it wrong (treating an allergy with topical antiseptic, or treating a hot spot with antihistamines alone) wastes time the inflammation doesn't have.
This is the UK guide to telling them apart, what each one usually responds to, and when to stop trying at home and ring the practice.
Photograph it now. Run it through the Superwild Skin Detective for an instant pattern-match against common UK dog skin conditions, plus tailored next steps. Free, no email needed.
The 30-second differential
Use this as your first orientation, then dig into the detail below.
| Feature | Hot spot | Allergy | Infection |
|---|---|---|---|
| Onset | Hours | Days/weeks | Days |
| Location | Single, focal | Multiple, symmetrical | Variable |
| Skin look | Wet, weeping, raw | Red, inflamed, often hairless | Crusty, scaly, pustules |
| Smell | Foul, often visible | Mild | Yeasty/musty (yeast) or sweet (bacterial) |
| Itch level | Severe, focal | Moderate to severe, generalised | Variable |
Hot spots (acute moist dermatitis)
What they are: a self-perpetuating skin lesion. Something starts the itch (a flea bite, an insect sting, a wet ear, a tangled mat), the dog scratches or licks, the skin breaks down, bacteria move in, and within hours you have a red, raw, weeping patch.
Classic UK presentation: a single spot, often on the face, neck, hip, or base of tail. Wet, sometimes pus-filled. Frequently surrounded by matted, smelly fur. Severely itchy — the dog will not leave it alone. Common after wet weather, swimming, grooming, or in dogs with thick coats (Golden Retrievers, Newfoundlands, German Shepherds).
What works: hot spots almost always need a vet. Treatment typically involves clipping the fur around the lesion, cleaning with antiseptic (chlorhexidine), topical or oral antibiotics, and a buster collar to prevent further self-trauma. Pain relief and short-course steroids may be prescribed.
Don't: apply human creams (Sudocrem, Savlon, hydrocortisone) without vet advice — many contain ingredients dogs lick off and react to.
Allergies
What they are: an immune-mediated reaction to an environmental allergen (pollen, dust mites, mould), a food protein, or insect saliva (flea allergy dermatitis). The classic UK clinical name is canine atopic dermatitis.
Classic UK presentation: generalised itchiness, often worse in spring and summer. Common spots: belly, armpits, groin, ears, between the toes (look for them licking their paws), face. Skin is red, often hairless from chronic licking, sometimes thickened and pigmented in long-standing cases. Multiple sites at once, often symmetrical (both armpits, both ears).
Higher-risk UK breeds: West Highland White Terriers, French Bulldogs, English Bulldogs, Cocker Spaniels, Labradors, Golden Retrievers, Boxers.
What works: identify and remove the trigger if possible (food trial, flea control). Long-term management often involves prescription medication (Apoquel, Cytopoint), antihistamines (limited effectiveness in dogs), medicated shampoos, and sometimes immunotherapy (allergy shots). Allergies are managed, not cured.
Bacterial and yeast infections (pyoderma, Malassezia)
What they are: overgrowth of bacteria (often Staphylococcus pseudintermedius) or yeast (Malassezia) on skin where the natural barrier has broken down. Frequently secondary to allergy or hot spots — the underlying immune issue is what let the infection take hold.
Classic UK presentation:
- Bacterial pyoderma: small pustules (look like pimples), crusts, hairless patches, sometimes a sweet smell. Often in skin folds (Bulldog faces, Pug faces, between toes, under the tail).
- Malassezia (yeast): red, greasy, foul-smelling skin (often a yeasty-bread or musty smell), particularly in the ears, between the toes, in skin folds, and on the belly. Itchy.
What works: diagnosis usually needs a skin scrape or tape impression at the vet. Treatment depends on the organism — antibacterial or antifungal shampoos, topical creams, sometimes systemic antibiotics or antifungals. The underlying cause needs treating too — otherwise the infection comes back as soon as the medication stops.
When to see a vet — UK guide
Same-day call for any of:
- Fast-spreading red wet patch (likely hot spot)
- Open sores, deep crusts, or visible pus
- Severe itch keeping your dog from sleeping
- Facial swelling alongside skin signs
- Lethargy or off food alongside skin issues
Routine appointment within 1–2 weeks for ongoing itchiness, recurring red patches, smelly ears, paw-licking, hair loss, or any skin issue lasting more than 7 days.
Skin disease in dogs almost never resolves with home care alone once it's been there more than a week. Get it diagnosed.
What you can safely do at home before the vet
- Photograph the lesion — especially useful if it changes between now and the appointment. Date the photos.
- Check for fleas — flea allergy dermatitis is one of the most common UK skin causes. Use a flea comb on a white surface; black specks that turn red when wet are flea dirt.
- Stop the licking/scratching — a buster collar (cone) until the vet visit prevents the self-trauma cycle that turns minor irritation into a hot spot.
- Don't apply human creams — many contain zinc oxide (Sudocrem) which is toxic if licked, or ingredients that mask infection.
Why this matters more than it seems
Skin disease in UK dogs is the second-most-common reason for vet visits after gastrointestinal complaints (BVA caseload data). Chronic allergic skin disease in particular is a quality-of-life condition — dogs who can't sleep because of itching are miserable. Getting the right diagnosis early changes the next 5 to 10 years of your dog's life.
How daily nutritional support fits in
Skin barrier health responds to nutritional baseline. Omega-3 fatty acids in particular have evidence supporting skin barrier function in atopic dogs. Super Everyday is Superwild's vet-developed daily powder, designed to support the seven pillars of canine wellness, including skin health, across the lifespan. It is not a treatment for hot spots, allergies, or infections, but a nutritional foundation that supports the underlying skin barrier.
Quick action. Use the Superwild Skin Detective to scan a skin lesion and get instant pattern-matched guidance. For the full 7-pillar wellness picture, take the Super Score quiz. And for ongoing daily nutritional support, Super Everyday is the foundation we recommend.
Frequently asked questions
How can I tell if my dog has a hot spot or an allergy?
Hot spots typically come on within hours, are a single focal patch (often on the face, neck, hip, or tail base), are wet/weeping/raw, and severely itchy in one spot. Allergies tend to come on over days or weeks, affect multiple sites symmetrically (belly, armpits, ears, paws), and produce more generalised itching. Hot spots almost always need a vet within 24 hours; allergies need a vet within 1–2 weeks.
What does a dog skin yeast infection smell like?
Malassezia yeast infections produce a distinctive musty, yeasty-bread, or fermented smell. Often most noticeable in the ears, between the toes, in skin folds, and on the belly. The smell typically gets worse with humidity and is often what tips UK owners off that something is wrong.
Can I treat a dog hot spot at home?
Hot spots almost always need a vet. The mainstay of treatment is clipping the fur around the lesion (so it can dry and breathe), cleaning with chlorhexidine antiseptic, topical or oral antibiotics, pain relief, and a buster collar to break the lick-scratch cycle. Home creams (Sudocrem, Savlon) often make things worse and can be toxic if licked.
What's the most common dog allergy in the UK?
Environmental allergies (canine atopic dermatitis) are the most common UK allergy presentation, with house dust mites, grass and tree pollen, and mould being the most frequent triggers. Flea allergy dermatitis is also extremely common and often missed. True food allergies are less common than owners think but do occur, particularly in young dogs.
Should I use Sudocrem on my dog's skin?
No. Sudocrem contains zinc oxide which is toxic to dogs if licked off (causes vomiting, diarrhoea, and in larger amounts can cause anaemia). Many other human topical products contain ingredients that are toxic to dogs or that mask diagnosis. Use vet-prescribed dog-specific topicals only.
Last updated April 2026. This guide is intended for general information and does not replace advice from a UK-registered MRCVS veterinarian. Persistent skin issues warrant veterinary assessment.
