Focal Alopecia in Dogs

In human beings, a full head of hair is commonly associated with youth and virility. Progressive or sudden hair loss, in many cases, is damaging to a person’s self-esteem, and a source of cosmetic concern. However, hair loss may be suggestive of some type of health disorder or disease process that requires investigation. As always, man’s best friend shares humankind’s health and lifestyle concerns, and often mirrors our unfortunate internal and external conditions. One such concern, alopecia (hair loss), is a common condition that affects the coats of all ages and breeds of dogs. Alopecia in dogs may simply be a frustrating cosmetic problem that might inflict misfortune on performance dogs or dogs purchased to meet a preferred breed standard. Hair thinning or excess shedding in your dog may also be simply seasonal in nature and part of the natural gain and loss of the coat, or, as with humans, indicative of advancement in age. 

Hair loss in your dog warrants a veterinary visit. At the appointment, your dog’s hair loss will be evaluated according to distinct characteristics, including the dog’s age, overall health status including any pre-existing conditions, location of the loss, degree of loss (whether substantial or sparse), and whether the onset is progressive or sudden. One characteristic of alopecia in dogs is the pattern of hair loss, whether the loss appears to be focal (occurring on one particular site on the body), multi-focal (occurring on more than one site on the body), or diffuse, meaning the fur is receding in an overall, diffused or symmetrical shed. Dogs presenting with focal or multi-focal alopecia are typically fighting an infection such as bacterial folliculitis, which can be successfully treated with antibiotics.

However, in other cases, hair loss may be secondary to a larger disease or disorder, such as parasites, a fungus, hormonal or endocrine imbalance, immune or genetic disorder, medication or vaccine side effect, nutritional deficiency, among other causes. No matter the reason, if you notice an uptick in shedding, recession of fur on large areas of the body, or patches/small areas of hair loss on your dog, a call to the veterinarian is recommended. Hair loss may be accompanied by itchy and inflamed skin, and such symptoms require care.

Focal alopecia in dogs occurs when the hair, or coat, of the dog sheds, thins or recedes in patches or sections, rather than in large areas or symmetrical patterns.

Focal alopecia will also appear as hair loss in patches, and small, localized areas. Occasionally, it may present with other symptoms such as:

• Scratching
• Redness
• Pustules
• Oiliness
• Crusty appearance
• “Hot spots”

Types

Hair loss or alopecia in dogs is categorized as focal, multi-focal or diffuse. Focal alopecia typically occurs secondary to a disorder or disease process, and has a patchy appearance. In focal alopecia, the dog may be suffering from parasitic bites or local infections, and will require treatment. In multi-focal alopecia, the dog will have more than one site of hair loss. When the hair loss is diffuse, it presents with a more symmetrical or “all-over” appearance, and may be due to seasonal changes or age.

There are multiple causes of hair loss in dogs. Many dogs lose hair due to parasites, such as fleas and ticks, so it’s important to keep your dog protected annually and the environment clean.  Allergies to certain foods or environmental conditions or settings also lead to hair loss. 

Like humans, dogs display various responses to household stress, including excess noise or change in family size, a new pet or schedule. One such response is hair loss. 

A balanced diet is key to a healthy coat, including plenty of fresh water. A nutritional deficiency can lead to alopecia. Fungal and bacterial infections also cause hair loss, but typically present with other symptoms such as sores, redness, weeping and inflammation. 

Female dogs may suffer hair loss due to changes in estrogen levels. In this case, breeding is highly discouraged, and spaying is recommended. Genetic conditions may also cause hair loss.

Primary means of diagnosis include a physical examination, microscopic examination of hair and skin (biopsy), blood and urine testing (to determine if there is a hormonal or other medical condition causing the hair loss), and response to treatment. Sometimes, an antibiotic will be tried to see if it clears up focal alopecia.

Though humans also suffer from alopecia, treatments should not be shared between people and animals. Human hair loss medications are both ineffective in dogs, and dangerous. A dog with chronic alopecia should be sprayed or neutered to prevent passing on the condition. 

Veterinarians will recommend the best treatment for your dog. This may include medication for an infection. Focal alopecia will often recede on its own, or respond to consistent care such as shampoos and conditioners, humectants and sprays. If the focal alopecia is secondary to a disease process, treatment will be specific for that cause.

Recovery and maintenance will depend upon the primary cause of alopecia. If there is an underlying condition, that will be treated apart from the localized hair loss. 

In some cases, the hair will regrow, but in other cases, the hair loss may be permanent. Alopecia may not always be cured, but it can be controlled enough to ensure that your pet is comfortable. It is highly recommended to spay or neuter a pet with alopecia.