Hair loss / bald patches in dogs: what to do
Symmetrical hair loss often points to endocrine disease; circular patches suggest fungal infection.
What are the common causes?
Hypothyroidism
Monitor for 48 hoursA slowed metabolism in middle-aged dogs: weight gain, symmetrical hair loss, dander, low energy.
Flea allergy dermatitis
Monitor for 48 hoursAn allergic reaction to flea saliva — a single flea bite can trigger intense itching.
Cushing's syndrome (hyperadrenocorticism)
Monitor for 48 hoursChronically high cortisol — common in senior dogs: symmetrical hair loss + increased drinking + pot-belly.
Allergic dermatitis (atopy)
Monitor for 48 hoursA chronic skin inflammation allergic to pollen, dust mites or food proteins — paw licking is the classic sign.
Acute moist dermatitis (hot spot)
Monitor for 48 hoursA moist red sore that expands within hours of licking/scratching — most common in warm, humid months.
Home care & observation tips
- ✓Track the weight trend
- ✓Get a thyroid panel
- ✓If diagnosed, medicate on schedule and re-test regularly
- ✓Treat ALL pets in the household for fleas
- ✓Clean the environment (hot-wash bedding, vacuum)
- ✓Use an e-collar to prevent scratching damage
When must you see a vet?
- ⚠Unexplained weight gain + hair loss + low energy
- ⚠Skin infections that never fully heal
- ⚠Widespread broken, infected skin
- ⚠Puppy anemia from fleas (pale gums)
- ⚠Increased drinking + symmetrical hair loss together
- ⚠Signs appearing while on steroid medication
FAQ
Is hair loss / bald patches in dogs serious?
It depends on the combination of symptoms, how long it has lasted, and your pet's energy and appetite.It is often linked to mild issues, but if nothing improves within 48 hours a vet visit is warranted. Enter the full symptom combination in our symptom checker for a more specific urgency assessment.
Can I monitor at home first? What should I watch?
If energy and appetite are normal with no other signs, 24-48 hours of monitoring is reasonable. Keep notes on frequency, duration, appetite, water intake, energy and what the stool/urine looks like — vets find this very useful.
What should I prepare before the clinic?
Note when the symptom started and how it changed; bring packaging or residue if ingestion is suspected; bring vaccination and deworming records; and if possible take a video (odd gait, cough sound) — clearer than describing.
Not sure how serious it is? Assess it with the symptom checker
Start symptom check →