Iatrogenic and Pseudo-Cushing’s in Dogs


A very small percentage of Cushing’s cases result from medical treatments for other conditions, such as the use of prednisone or other corticosteroid medications to control allergies, arthritis, or autoimmune conditions. This is called “iatrogenic” (doctor-caused) Cushing’s. In these cases, the Cushing’s is treated by gradual discontinuation of the corticosteroid drugs (if the drugs are withdrawn too quickly, an Addisonian crisis can result). Patients can take as long as three months to recover after corticosteroid drugs are stopped.

Also known as Alopecia X, pseudo-Cushing’s is identified by symmetrical alopecia (hair loss) on the trunk of the body, thighs, or neck, along with darkening of the skin where hair is lost. The coat’s color may change as well. The condition does not cause itching.

Pseudo-Cushing’s is seen in young dogs (ages 1 to 5) with plush coats, such as Pomeranians, Poodles, Samoyeds, Alaskan Malamutes, and Siberian Huskies. Pseudo-Cushing’s is thought to be a mild form of pituitary-dependent hyperadrenocorticism.

Dogs with this disorder may respond to castration, methyltestosterone, melatonin, growth hormone supplementation, or one of the drugs used to treat Cushing’s disease. One study showed that 90 percent of dogs with pseudo-Cushing’s treated with trilostane responded within eight weeks.