Why Is My Dog Losing Hair

This page is educational reference material for preparing questions. A licensed veterinarian examines the animal, makes the diagnosis, and sets the treatment.

Dog hair loss causes: allergies, hormonal imbalances, infections, stress, and parasites. Diagnosis and treatment options.

Understanding This Symptom

The dog who seems "a bit off" today is giving you the earliest possible warning — and the version of you that notices early is the version that saves money and suffering later. This page covers the most common causes, warning signs that indicate an emergency, and what you can expect at the veterinarian.

Common Causes

Less Serious Causes

More Serious Causes

• Poisoning or toxic exposure

What to Watch For

• Lethargy or reluctance to move or play
• Vomiting, diarrhea, or changes in stool

Home Care and First Steps

Veterinary Diagnosis

Your veterinarian will typically:

• Perform a thorough physical examination

Treatment Options

Prevention

Long-Term Management

When to Get a Second Opinion

Related Symptom Guides

• Why Is My Dog Not Eating?
• Why Is My Dog Shaking?
• Why Is My Dog Limping?
• Why Is My Dog Vomiting?
• Why Is My Dog Coughing?

Should I go to the emergency vet?

Go sooner if the hair loss comes with a rash that is spreading by the hour, facial swelling, or a dog that is also lethargic and drinking heavily. Symmetric coat loss in a dog that feels fine can wait for a regular dermatology-style appointment.

How much will treatment cost?

The workup often includes a skin scraping for mites, a fungal culture or lamp check, and bloodwork when the pattern looks hormonal. Cytology is cheaper than a biopsy. Ask the order the clinic wants before you approve all of it.

Can I treat this at home?

Note whether the dog is itchy, whether the skin is greasy or smooth, and which areas are bald. Stop any new topical oil or dip. A bald patch that is also scabby can be ringworm, which spreads to people, so wash hands after handling.