Pemphigus is a skin disease characterised by blisters and erosions, often accompanied by scratching and crusting. A skin biopsy and veterinary evaluation are needed to confirm the diagnosis — ask your vet to arrange the appropriate tests.

It looks like a skin infection — what other tests might be needed?

Your vet will typically perform skin scraping and cytology, and blood and biochemistry panels. A biopsy may be taken if needed for a definitive diagnosis. The specific tests will be determined by your vet.

How long does it take for treatment to work?

The time for improvement varies depending on the severity and treatment approach. Some cases show progress within a few weeks, but long-term monitoring is usually required — follow your vet's guidance for regular check-ups.

What information should I bring to the appointment?

It is helpful to bring photos or videos of the lesions, a timeline of when symptoms began, and records of current medications and daily food intake. This allows the vet to assess the situation and arrange tests more efficiently.

How much do the tests and treatment usually cost?

Costs vary by clinic and region — ask your vet for an estimate before proceeding.

Disease Guide

Pemphigus in Dogs & Cats: Skin Blisters, Diagnosis & Home Care Guide [2025]

An autoimmune skin disease requiring long-term medication management

Take 1 minute to check the symptoms first

Last updated: 2026/01/06

Pethealthmap Editorial Team

Sources: WSAVA, ISFM, AVMA

When to See a Vet

Seek Immediate Veterinary Care (Emergency)

•Large areas of skin ulceration or exposed tissue
•Persistent high fever with extreme lethargy and no appetite
•Severe ulceration of the mouth or face affecting eating

Schedule a Veterinary Visit Soon (Within 24-72 Hours)

•Localized recurrent blisters or scabs that are not healing
•Persistent scratching causing broken skin and discharge
•Marked decrease in food intake and activity level

01What symptoms indicate something is wrong?

Pemphigus primarily affects the skin, with blisters, crusting, hair loss, and general discomfort being the most common signs; appetite and energy changes may also occur.

Blisters, erosions, or crusting on one or multiple areas of the skin
Redness, swelling, hair loss, and noticeable scratching or itching
Discharge or odour from skin lesions, with risk of secondary infection
Reduced appetite or changes in eating behaviour in some cases
Fever, lethargy, or a noticeable drop in energy levels
Localised pain, flinching when touched, or difficulty moving

Seek emergency care immediately if you notice the following symptoms:

⚠️ Persistent high fever with extreme lethargy and no appetite
⚠️ Large areas of skin erosion or exposed tissue
⚠️ Severe oral or facial ulceration affecting the ability to eat

02How to assess abnormalities at home: what to observe and when to seek emergency care

Keeping detailed home observations helps the vet quickly assess disease progression and treatment response.

Record when skin lesions were first noticed and how they have changed over time
Take close-up and full-body photos of the lesions and video any scratching behaviour
Track daily food intake, water consumption, and energy levels
Take your pet's temperature daily and note the reading and time
Observe toileting habits, gait, and any reluctance to have lesions touched
Seek immediate veterinary attention if symptoms worsen rapidly or there is heavy discharge from lesions

03How will the vet make a diagnosis? Common diagnostic tests

The vet will focus on skin examination and laboratory tests, using a biopsy when necessary to confirm the diagnosis and assess systemic involvement.

Full physical examination

assessing the skin, mucous membranes, and overall condition

Skin scraping and cytology

to assess signs of inflammation or infection

Skin or mucosal biopsy (histopathology) for a definitive diagnosis

Blood and biochemistry panels

to evaluate organ function and inflammatory markers

Imaging (such as X-ray or CT) or specialist referral if needed to aid assessment

04What treatment and care are needed after diagnosis? Medication, diet, and home management

Pemphigus typically requires ongoing medication and long-term monitoring; consistent home care and regular check-ups help reduce the risk of complications.

Medications to control the immune response and prevent infection, as directed by your vet
Short-term treatment for bacterial infection if secondary infection is present
Regular follow-up visits to monitor skin and blood changes as instructed
Dietary adjustments to support nutrition or a hypoallergenic diet if recommended by your vet
Prevent your pet from scratching and keep lesions clean and dry at home
A dermatology specialist evaluation is recommended for recurrent or complex cases

05What should you prepare before the vet visit? Key information to help the vet assess quickly

Note the onset date and how symptoms have progressed over time

Keep a complete record of food intake, water consumption, and toileting

List all current and past medications and supplements

Bring photos or videos of the lesions, including any scratching or behavioural changes

Call ahead to book an appointment and mention whether a dermatology specialist consultation may be needed

This content is for reference only and cannot replace a professional veterinary diagnosis. If your pet shows signs of illness, please seek veterinary care promptly.