What is a hotspot on a dog?

Hotspots—those sudden, raw, wet patches on a dog’s skin—matter because they are painful, progress fast, and can change how you groom, travel with, or care for a dog; noticing them early often means less stress for the animal and owner, and fewer vet bills down the road.

Why every dog owner should understand hotspots

Hotspots are more than a nuisance: they can make a dog intensely uncomfortable and interfere with daily life. I typically see owners who first notice a patch of damp fur or constant licking when they return from a weekend at the lake, after a warm, humid spell, or following a grooming session that left mats or irritated the skin. Left unchecked, a small area of irritation can become a much larger wound in a day or two, leading to pain, missed walks, and the need for medications or bandaging. For anyone who travels with their dog, takes them swimming, or struggles with seasonal allergies or flea control, hotspots are a recurring concern that affects grooming choices, crate or bedding hygiene, and when you should book a vet visit.

What exactly is a hotspot?

A hotspot is a common lay term for acute moist pyotraumatic dermatitis: a rapidly developing, red, wet, often oozing and intensely itchy patch of skin that appears when a dog repeatedly licks, chews, or scratches at a spot. These lesions commonly look raw, may smell faintly of infection, and can expand quickly over 24–48 hours. The immediate priority when you spot one is to stop the licking—both to reduce pain and to limit further tissue damage—and to assess how severe the lesion looks so you can decide whether home care or prompt veterinary attention is needed.

Skin-level changes: what happens during a hotspot

Under the skin’s surface there is a chain of events that often explains the speed and severity of hotspots. A small trigger—an insect bite, a scratch under a mat, or an allergic itch—leads a dog to lick or chew. That self-trauma breaks down the skin barrier, allowing bacteria that normally live on the skin to overgrow and inflame the area. Inflammation brings more moisture and exudate, which the dog then licks away, perpetuating the cycle. Because the wound is kept moist and continually disturbed, normal healing processes struggle to re-establish the skin’s protective layer, so the lesion can remain open and painful until the cycle is broken.

When and why hotspots tend to flare up

Hotspots tend to arise in predictable situations. Warm weather and high humidity create a skin environment that favors bacterial overgrowth, so hotspots are commonly seen in summer months. Parasites like fleas, ticks, or mites may create a focal itch that a dog obsessively targets. Underlying skin conditions—seasonal or food allergies, yeast or bacterial skin disease—are frequently linked to hotspots because they raise baseline itch levels. Practical triggers include wet fur left matted after swimming or bathing and stress-related licking during changes in routine, travel, vet visits, or kennel stays. In short, hotspots are most likely when irritation, moisture, and opportunity to self-traumatize coincide.

Warning signs that require prompt veterinary attention

Not every hotspot is an emergency, but several signs suggest you should seek urgent veterinary care. Rapidly expanding lesions or deep ulcers that seem to involve deeper tissues may indicate a more serious infection; systemic signs such as fever, marked lethargy, or inappetence may suggest the dog is ill beyond the skin; severe pain, active bleeding, or areas that appear blackened or necrotic are worrisome. Lesions close to the eyes, mouth, genitals, or those spreading despite simple home care may be complicated by secondary cellulitis or require systemic treatment—these are situations where prompt veterinary assessment is sensible.

First steps to take when you discover a hotspot

When you first find a hotspot, a calm, methodical approach helps. Assess how large the area is, how much your dog tolerates handling, and whether the dog is in pain—some dogs will flinch or snap if the area is very sore. If the dog will allow it, clip the hair around the lesion gently (short strokes; secure footing) to expose the skin and allow the area to dry. Lightly clean the spot with a vet-recommended antiseptic—many veterinarians advise a dilute chlorhexidine solution or a gentle antiseptic wipe—avoiding harsh scrubbing. Crucially, prevent further licking; an Elizabethan collar or a comfortable inflatable alternative is often the easiest immediate step. If the lesion is small, not very painful, and your vet is available for a quick consult, you may be advised to continue local care at home; if it’s large, deep, very painful, rapidly growing, or the dog is systemically unwell, contact your veterinarian promptly for assessment and likely prescription therapy.

At-home fixes: environment and training to reduce recurrences

Reducing future hotspots usually means addressing both environment and behavior. Regular grooming to prevent mats, and careful drying after swimming or baths, lowers the chance that trapped moisture or friction will trigger a hotspot. Consistent parasite control—fleas and ticks—reduces the risk of focal itching that can start a problem. If allergies are suspected, a veterinary plan for diagnosis and long-term control is likely to reduce hot spot frequency. For dogs that lick obsessively for behavioral reasons, simple enrichment and training can help: increase interactive play, scatter feeding, sniffing walks, puzzle feeders, and teach an alternative behavior such as a settle-on-mat cue. In anxious dogs, working with a behavior-focused trainer or veterinarian may be necessary to reduce stress-related self-trauma.

Protective gear and safe products to aid healing

Certain tools make managing a hotspot safer and more comfortable. An Elizabethan collar (cone) remains a reliable way to stop licking; inflatable collars are a softer option that may be tolerated better but are not always effective for a lesion on the neck or shoulder. A good pair of grooming clippers and blunt-nosed stainless scissors let you carefully remove surrounding hair without tugging; if you’re unsure, have a professional groomer or vet perform the clipping. Use vet-approved antiseptic cleansers rather than household products, and when bandaging is advised, pick non-stick dressings and clean absorbent pads with a secure but not tight wrap—bandaging should generally be done or approved by a professional to avoid circulation problems or further trapping moisture.

Sources and further reading

• Merck Veterinary Manual: “Pyotraumatic dermatitis (Hot Spots)” — Merck Veterinary Manual clinical overview and treatment guidance.
• Scott DW, Miller WH, Griffin CE. Small Animal Dermatology — comprehensive textbook on canine skin disease and management.
• American Veterinary Medical Association (AVMA): Client information on pyotraumatic dermatitis and wound care recommendations.
• Olivry T., DeBoer D. J., et al. (2015). “Treatment of Canine Atopic Dermatitis: Clinical Guidelines” — Veterinary Dermatology (international consensus on allergic skin disease management).