What causes depigmentation in dogs and cats?

Depigmentation can be related to immune reactions, chronic inflammation, infection, or genetic factors. The specific cause requires veterinary examination — including blood tests, skin evaluation, or biopsy — to determine. It is advisable to consult your vet for a full assessment.

What home care should I try first for skin itching?

Start by recording the frequency of itching, photographing the lesions, and preventing your pet from coming into contact with new foods or suspected allergens. If itching persists or the skin breaks down, seek veterinary care promptly.

Does a skin biopsy require anaesthesia?

Small, superficial biopsies can sometimes be performed under local anaesthesia, while deeper or larger biopsies may require general anaesthesia. Whether anaesthesia is needed depends on the individual case and the extent of the procedure — discuss this with the performing vet.

Can depigmentation be passed on to other animals or people?

Depigmentation itself is generally not contagious, but if it is caused by infection (such as fungal or bacterial), there may be a risk of transmission. Have your vet confirm the underlying cause and follow their recommended management.

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

Skin Depigmentation in Dogs & Cats: Symptoms, Diagnosis & Care Guide [2025]

Depigmentation skin disorders can stem from immune, infectious, or congenital causes — treatment requires identifying the underlying cause first.

Take 1 minute to check the symptoms first

Last updated: 2026/01/05

Pethealthmap Editorial Team

Sources: WSAVA, AAHA, National Taiwan University Veterinary Hospital

When to See a Vet

Seek immediate veterinary care (emergency)

•Large areas of skin are ulcerated and continue to bleed heavily without stopping
•Severe lethargy, refusal to eat, or fainting occurs
•Rapid breathing or obvious bluish discoloration of the lips or gums

Schedule a clinic visit soon (within 24-72 hours)

•Long-term itching has caused severe hair and coat loss
•Localized skin repeatedly becomes red and swollen or has abnormal discharge
•Skin color has changed noticeably and the affected area is gradually expanding

01What symptoms should you watch out for?

Skin disease and depigmentation often appear as changes in your pet's appearance and daily behaviour, including localised or generalised coat colour changes and abnormal behaviours.

Persistent or recurring itching — frequently scratching or biting the same spot with paws or mouth
Localised or widespread whitening of the coat, colour fading, or uneven pigmentation
Hair loss, visible dandruff, or reddened, inflamed skin
Lethargy or reduced activity, decreased appetite
Frequent licking of the affected area or changes in toileting habits
Skin ulceration, foul odour, or abnormal discharge

Seek emergency care immediately if you notice the following symptoms:

⚠️ Large areas of skin ulceration with persistent heavy bleeding
⚠️ Severe lethargy, refusal to eat, or fainting
⚠️ Rapid breathing or obvious purple/blue discolouration of the lips and gums

02How to assess changes at home: key observations and emergency criteria

Recording clear photos and behavioural changes at home can help your vet identify possible causes more quickly.

Take daily close-up and full-body photos of the lesions and note the time they were taken
Record how often and when scratching, biting, or licking occurs
Monitor and record changes in weight, food intake, and water consumption
Watch for any changes in bowel or bladder habits and note them down
List any recently introduced foods, medications, or environmental changes
If symptoms worsen, arrange a vet consultation as soon as possible

03How will the vet diagnose this condition? Common diagnostic tests

At the clinic, your vet will perform a physical and laboratory examination to confirm infection, inflammation, or other causes, and arrange further tests if needed.

Physical examination

assessing the skin, lymph nodes, and overall condition

Skin scraping or cytology

checking for parasites or signs of infection

Tissue biopsy

examining cell structure and pathological changes

Bacterial or fungal culture

identifying potential causative bacteria or fungi

Blood tests

assessing overall health and inflammatory markers

04Post-diagnosis treatment and care: medications, dietary adjustments, and care guidelines

Treatment involves medications alongside environmental and dietary adjustments, tailored to the diagnosis, with regular follow-up visits to monitor progress and side effects.

Systemic or topical medications and care recommendations based on test results
Short-term corticosteroids or other medications require veterinary supervision and monitoring
Adjust diet and minimise exposure to suspected allergens
Follow your vet's instructions for home cleaning and wound care
Attend regular follow-up appointments to assess treatment response and arrange any necessary monitoring
If symptoms do not improve, referral to a veterinary dermatology specialist may be recommended

05What to prepare before the vet visit: key information to help your vet diagnose quickly

Take close-up and full-body photos of the lesions and note when each was taken

Write down when symptoms first appeared and how they have progressed

Record the frequency of scratching, licking, and whether any bleeding has occurred

List any recent changes to food, medications, or the environment

Bring any previous test reports or a list of medications your pet has taken, if available

Book in advance at a clinic that can perform skin examinations or biopsies

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.