This is a rare cause of bilateral symmetrical hair loss. Growth hormone (somatotropin) is secreted by the pituitary gland. In some cases, for unknown reasons, the pituitary does not manufacture or release adequate concentrations of growth hormone, resulting in coat and skin changes similar to those described for hyerperestrogenism. Symptoms generally appear at puberty, but may occur at any age.
This disease has been observed in Pomeranians, Chow Chows, Poodles, Samoyeds, Keeshonds, and American Water Spaniels. It occurs predominantly in male dogs.
Treatment: It is important to exclude other hormone-dependent causes of hair loss. The treatment of choice for growth hormone–responsive alopecia is neutering. If the coat does not improve, the dog may respond to growth hormone administered subcutaneously three time a week for four to six weeks. Dogs receiving growth hormone must be monitored for the development of diabetes mellitus.