Hyperpigmentation is a secondary condition that usually occurs due to an existing primary issue. While hyperpigmentation itself is not harmful to the dog, you should seek veterinary care in order to rule out any serious health issues.
Note hyperpigmentation by a darkening of the dog's skin, which may be accompanied by mild to severe hair loss or total baldness.
Causes of canine hyperpigmentation can vary and include allergic reactions, adrenal gland diseases, cancerous or benign growths and inherited disorders such as Black Hair Follicular Dysplasia.
Due to a high number of potential causes, several diagnostic tests including blood tests, urinalysis or biopsies may be performed to determine the underlying cause of hyperpigmentation.
Treatment varies based on the results of diagnostic tests. For example, if an adrenal gland tumor is the cause, then surgical removal of the tumor will be necessary.
Fortunately, hyperpigmentation itself is not a cause of major concern. With successful treatment of the underlying condition, the dog will continue to live a long and happy life. However, owners should be aware that hyperpigmentation may or may not be permanent for some dogs.