Cat symptom
Hair loss / bald patches in cats
Thinning fur or bald spots. Often linked to itching and over-grooming, but some causes are hormonal and aren't itchy at all.
Common causes of hair loss / bald patches in cats
- Parasites (fleas, mange mites) and the scratching they cause
- Allergies and the resulting over-grooming (common in cats)
- Ringworm (a fungal infection — can spread to people)
- Hormonal or endocrine disease (hypothyroidism in dogs, Cushing's disease, or hyperthyroidism-related coat changes in cats)
Who's most at risk
- Pets with fleas or allergies
- Young, old, or immunocompromised pets (ringworm)
- Breeds prone to hormonal disease
- Multi-pet homes (contagious causes)
What you can do at home
- Maintain flea prevention and avoid known allergens where possible
- Don't share bedding/brushes between pets until ringworm is ruled out
- Photograph the patches over time to show your vet the progression
When to see a vet
- Spreading bald patches, redness, or sores
- Hair loss with weight, energy, or thirst changes (possible hormonal disease)
- Anyone in the household develops a circular, itchy rash (possible ringworm)
When it's more serious
- Spreading or inflamed patches need a vet workup soon.
- Hair loss with these signs can signal hormonal disease — ask about bloodwork.
- That can indicate ringworm spreading to people — see your vet and your doctor.
What your vet may do
- Skin exam, a fungal (ringworm) test, and cytology
- Check for parasites and skin infection
- Bloodwork if a hormonal cause is suspected
- Treat the specific cause; isolate if ringworm
Questions to ask your vet
- Could this be ringworm — and is it contagious to us?
- Is a hormonal disease possible?
- What testing makes sense first?
- How long until the coat recovers?
Frequently asked questions
What causes hair loss / bald patches in cats?
Thinning fur or bald spots. Often linked to itching and over-grooming, but some causes are hormonal and aren't itchy at all. Common causes include: Parasites (fleas, mange mites) and the scratching they cause; Allergies and the resulting over-grooming (common in cats); Ringworm (a fungal infection — can spread to people); Hormonal or endocrine disease (hypothyroidism in dogs, Cushing's disease, or hyperthyroidism-related coat changes in cats).
Is hair loss / bald patches in cats an emergency?
Book a veterinary visit soon. See a vet right away if: Spreading bald patches, redness, or sores; Hair loss with weight, energy, or thirst changes (possible hormonal disease); Anyone in the household develops a circular, itchy rash (possible ringworm).
What can I do at home for a cat with hair loss / bald patches?
Maintain flea prevention and avoid known allergens where possible Don't share bedding/brushes between pets until ringworm is ruled out Photograph the patches over time to show your vet the progression
Sources
Related reading from Webvet
Reviewed by the Webvet Veterinarian Team
This guide is general information, not a diagnosis, and does not replace an exam by your veterinarian. If your pet is in distress, contact your vet or an emergency clinic right away.