This disease is often confused with Cushing's disease, which is often seen in other species. The difference is which layer of the adrenal gland that is affected. With Cushing's disease, the Fasiculata layer releases too much glucocorticoids. In ferrets however, it is the inner layer, the Reticularis that is affected. Because this layer releases sex hormones, the ferret will begin to show signs as if it were still intact. The female's vulva will swell and males will show sexual aggression and attempt to mate. Hair loss begins at the base of the tail, and can progress until the entire body is bald, except for the feet and the face.

This can be surgically corrected, by having the affected adrenal gland removed. Sometimes the remaining adrenal glad will become affected later, but it can be removed as needed. Usually enough adrenal tissue remains in the body to maintain the body's electrolytes and glucocorticoids, but after having the remaining adrenal gland removed, the ferret is usually sent home on oral medications to help regulate electrolytes and they are gradually weaned off.

This disease is very rare among ferrets in Europe, and some people speculate that because ferrets are most often housed indoors in North America, thus exposing them to artificial lighting, they do not get the seasonal break from long summer daylight hours. Some people are attempting to provide their ferrets with a dark sleeping space and turning the room lights off in the ferrets' room in the evening to keep their "daylight hours" below 14 hours a day. No harm can come of this, but because there is yet no evidence that this will truly prevent adrenal disease, it is not widely recommended.