Introduction
Over fifty different types of conditions are known to cause alopecia in dogs. However, the most common causes of alopecia in dogs include: parasites, hormonal imbalances, and allergies.
Causes of Hair Loss in Dogs
Parasites
Parasites are notorious for causing alopecia in dogs. Fleas, ticks, lice, and mites can all cause intense itching and scratching which leads to hair loss. Parasites can also damage hair follicles, and allergic reactions to the parasites may cause hair loss as well.
Hormonal Imbalances
Hormonal imbalances that are caused by conditions which include Cushing’s disease, hyperestrogenism, hyperthyroidism, and hypoandrogenism, will all result in some form of alopecia if the condition is not brought under control.
Allergies
Allergies to foods, chemicals, pollens, grasses, and other types of allergens may also cause hair loss in dogs.
Inherited Conditions
Some types of alopecia are an inherited condition that is passed onto the dog from genes that are carried by the mother and/or father. These types of inherited alopecia conditions include: acanthosis nigricans, black hair follicular dysplasia, color dilution mutant alopecia, congenital hypotrichosis, and pituitary dwarfism.
Reactions to Medication
Alopecia may also be caused by a reaction to certain types of medication. Chemotherapy can cause alopecia, and there is also a type of alopecia known as drug or injection reaction alopecia that is caused by an allergic reaction to a medication or vaccine.
Nutritional Deficiency
In some cases alopecia is caused by severe stress or nutritional deficiencies. Dogs that are nursing puppies can develop a condition that is known as ‘blowing her coat.’ This is caused by nutritional, and even emotional, stress that nursing places on the mother’s body. Dogs that are anxious, have mental disorders, or who have had abusive backgrounds may also develop hair loss as a result of emotional and psychological stress.