Horse Illustrated Magazine

Cushing’s syndrome (hyperadrenocorticism)

What it is: Cushing’s, now called Pituitary pars intermedia dysfunction (PPID), is a disease caused by a benign tumor in the pituitary gland, which controls the entire endocrine system. It usually occurs in older horses but occasionally affects younger ones as well.

Symptoms: Lethargy; excessive drinking/urination; heavy, coarse coat; lack of shedding; pot belly; loss of muscle tone, especially over the topline; increased appetite without weight gain; chronic laminitis; and immune system abnormalities, which can lead to other health issues such as hoof abscesses, respiratory disease, skin infections and periodontal disease.

What to do: Cushing’s syndrome is not usually an emergency, so call your vet during regular clinic hours. If your horse suddenly develops signs of laminitis, call your vet immediately.

Outlook: Cushing’s syndrome isn’t curable, but it can be managed with medication and other measures, such as dietary changes and year-round body clipping.

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This article originally appeared in the 2012 issue of Horses USA.