Hair loss in dogs is a common complaint, especially on the back. Some breeds of dog are more susceptible than others such as Greyhounds, Terriers, Whippets, Chihuahuas, and Boxers. Females are also more often affected by hair loss. Some of the most common causes of hair loss on the back are:

Hair loss does not always indicate a problem. In fact, almost all dogs shed, especially during the summer months. However, if your dog has unexplained hair loss with other symptoms such as redness, itching, lesions, fever, or pain, it is a good idea to see your veterinary care provider.

There are many skin disorders that can cause your dog to lose hair on her back. Some of the most common include dry skin and dermatitis.

If your dog is suffering from depression or anxiety, she may be excessively grooming or licking, which creates hair loss. Stress can also cause hair loss.

Certain infections that may cause your dog to lose hair on her back include bacterial, fungal, and yeast. If the hair loss is accompanied by hot spots or pus, she probably has an infection.

There are many types of parasites and mites that can cause hair loss on the back. Examples are mange (from mites), fleas, ringworm, chiggers, and mosquitos.

Another cause of hair loss is an allergic reaction to food, medication, shampoo, or just about anything. This usually includes itching and possibly redness as well.  

Some forms of trauma such as a laceration or abrasion from an accident can create a patch of hair loss on the back. Also, when dogs are injured they sometimes lick the area, which can cause hair loss.

Some of the most common drugs that cause hair loss on the back of dogs include chemotherapy, vaccination reactions, and prednisone.  

There are some medical disorders that can cause hair loss on your dog’s back such as:

If your dog is losing hair on her back but has no other symptoms, it is probably nothing to worry about if it is mild. However, if she is losing a lot of hair or has other symptoms like itching, licking, biting, redness, lesions, nodules, or changes in skin color, you should call your veterinary care provider. Most of the time, you will need to bring your dog to the office for a physical examination to determine the exact cause of the hair loss. Dermatitis or dry skin can be treated with medication, ointment, or shampoo. Psychological issues can be handled with therapy or medication. Infections, parasites, or mites can be cured with medication. If your veterinarian determines your dog has alopecia, there are some medications that can be given, depending on the cause. Other medical disorders will need to be treated with medication or other types of therapy.

By brushing your dog regularly and taking her to see the veterinarian at least once per year, you should be able to prevent any serious hair loss. However, sometimes there is a sudden loss of hair caused by an illness or injury that you cannot prevent. If it is a psychological issue, that is often overlooked until the hair loss becomes more pronounced. To prevent parasites and mites, the veterinarian can provide you with medication such as flea and tick topical liquids, shampoo, or pills.

The cost of treating your dog for hair loss on her back ranges from about $350 for most skin disorders, infections, parasites, and mites. This includes an office visit, laboratory and diagnostic tests, and treatment. Allergies can cost up to $1,500 due to the difficulty in determining the cause of the allergy. Medical disorders range from $350 for alopecia to over $10,000 for cancer.