3 Common Causes Of Hair Loss In Dogs

If your dog is experiencing hair loss, they'll need to be examined by your vet, as hair loss is often a symptom of an underlying health problem. The pattern of hair loss and any accompanying symptoms, such as local inflammation and crusting around hairless patches of skin, can help your vet determine the cause of your dog's hair loss. Your vet will also take a skin cell sample from an affected area, and this will be analysed for the presence of mites, fungal spores and bacteria. Blood tests can be used to check for raised inflammatory markers, which would indicate the presence of an infection, and your dog's hormone levels. Here's an overview of three common causes of hair loss in dogs:


Mange is a skin condition that's caused by an infestation of tiny demodex mites that can be passed between dogs that come into physical contact with one another. Hair loss caused by mange is patchy in appearance and not confined to any particular area of your dog's body. Demodex mites can be identified during skin cell analysis, and mange is treated with a combination of oral and topical anti-parasitic drugs. Your dog will have to be kept away from other dogs while they have mange, and your vet will take further skin cell samples at the end of the treatment period to ensure the mites have been eradicated.


Ringworm is a fungal infection and is highly contagious. Hair loss caused by ringworm tends to occur on multiple areas of your dog's body and bald patches appear red and have crusts around the periphery. Ringworm is treated with antifungal ointment and medicated shampoo, which helps promote healing by calming inflamed skin. Your dog may want to lick the ointment off their skin, so your vet will provide a surgical collar for your dog to wear for the duration of the treatment.

Endocrine Disruption

If your dog's hormones are out of balance, their hair loss may have a symmetrical pattern to it. Too much oestrogen or low levels of testosterone can lead to hair loss, and your vet will check your dog's thyroid function if their hair loss appears to be hormone related. This type of hair loss can be treated with synthetic hormones, which are used to balance your dog's endocrine system. Your vet will carry out regular blood tests to check your dog is receiving the correct dosage of synthetic hormones.

If you notice even small bald patches or areas where your dog's hair has thinned considerably, schedule an appointment with your vet as soon as possible to prevent your dog experiencing unnecessary discomfort.