What are the common causes of papular and nodular skin disease?

It can be caused by a range of factors including bacterial or fungal infections, parasites, allergies, or immune-mediated reactions. A vet examination — such as skin scraping or biopsy — is needed to identify the specific cause and determine the best course of treatment.

Is a skin biopsy always necessary?

Not always. If the lesion is unclear, recurring, or suspected to be a tumour or chronic inflammatory condition, your vet will recommend a biopsy to establish a definitive diagnosis and guide the treatment plan.

What can I observe at home to help with diagnosis?

You can photograph or video the lesions, record when they appeared and how often your pet scratches, and note any changes in appetite or toileting. Sharing this information with your vet will aid the diagnostic process.

How often are follow-up visits needed?

The frequency of follow-up visits depends on the underlying cause and how well the condition responds to treatment. Mild infections or allergies may only need a check-up every few weeks, while chronic or complex cases may require long-term ongoing monitoring. Follow your vet's recommended schedule.

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

Papular & Nodular Skin Disease in Dogs & Cats: Symptoms, Diagnosis & Home Care [2025]

Papular and nodular skin disease refers to raised bumps or lumps on the skin that may be caused by infections, allergies, tumours, or autoimmune conditions. A definitive diagnosis typically requires a skin biopsy, after which targeted treatment can be planned.

Take 1 minute to check the symptoms first

Last updated: 2026/01/05

Pethealthmap Editorial Team

Sources: WSAVA, AVMA, National Taiwan University Veterinary Hospital

When to See a Vet

Seek immediate veterinary care (emergency)

•Rapid breathing, open-mouth breathing, or obvious wheezing
•Sudden collapse, unresponsiveness, or loss of consciousness
•Heavy skin bleeding or rapidly expanding swelling

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

•New papules or palpable nodules on the skin
•Frequent scratching or chewing causing persistent skin breaks
•Reduced appetite, decreased water intake, or lower activity level

01What Symptoms Indicate Something Is Wrong?

Papular and nodular skin disease can present with both skin lesions and general systemic signs that may affect your pet's energy and eating habits. Below are changes that owners most commonly notice.

Reduced activity or lower energy than usual
Decreased appetite or changes in eating habits
Small raised papules or palpable lumps/nodules on the skin
Repeated scratching, licking, or chewing at affected areas
Changes in toileting habits or short-term weight fluctuations

Seek emergency care immediately if you notice the following symptoms:

⚠️ Rapid breathing, open-mouth breathing, or audible wheezing
⚠️ Sudden collapse, unresponsiveness, or loss of consciousness
⚠️ Heavy bleeding from the skin or rapidly spreading swelling

02How to Assess Abnormalities at Home: Observation Tips & Emergency Guidelines

Gathering and recording information before your vet visit can help your vet understand the condition faster and arrange appropriate tests.

Note when the signs first appeared and how they have changed over time
Take front, side, and close-up photos or videos of the lesions
Track how often your pet scratches or licks, and when it seems worse
Monitor and record any changes in appetite, water intake, and toileting
Weigh your pet at home to confirm any short-term weight changes

03How Will the Vet Diagnose This? Common Examinations and Tests

Your vet will use a physical examination along with laboratory or imaging tests to identify the underlying cause and develop a treatment and monitoring plan.

Physical examination

palpation of the skin and lymph nodes to assess pain and the extent of the lesions

Skin scraping

to check for parasites, fungi, or other micro-organisms

Cytology

microscopic examination of cells to identify inflammation or infection

Skin biopsy

histopathological examination to rule out tumours or chronic lesions

Bacterial culture

to identify the causative bacteria and test antibiotic sensitivity to guide treatment

Advanced imaging (CT/MRI)

to evaluate deep-seated or complex lesions

04What Treatment and Care Are Needed After Diagnosis? Medication, Diet & Home Care Guide

Treatment will be tailored to the underlying cause and test results, and may include medication, supportive care, and long-term follow-up.

Medication (short-term or long-term) adjusted according to test results
Hospitalisation for monitoring and supportive care may be needed in severe cases
Dietary adjustments or allergen management may be used as complementary measures
Regular check-ups to monitor skin lesions and blood tests as required
Referral to a veterinary dermatologist is recommended for complex or persistent cases

05What to Prepare Before the Vet Visit: Key Information to Help Your Vet

Bring photos and videos of the lesions, including comparisons from different time points

Prepare a timeline of when the condition started and how symptoms have fluctuated

Note the frequency of scratching and when it tends to be worse

Describe any recent changes to diet, medication, or environment

Bring a list of all current medications and supplements your pet is taking

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.