Cushing’s Disease (PPID)

Cushing’s disease (PPID) occurs when neurons in the hypothalamus degenerate, reducing dopamine production. This loss of dopamine allows the pars intermedia of the pituitary gland to become overactive, producing excess adrenocorticotropic hormone (ACTH), which in turn stimulates the adrenal glands to increase cortisol production. The condition is most common in horses over 15 years old, though it can occasionally affect horses as young as 5 to 7 years. All breeds and genders can be affected, but ponies and Morgan horses may be predisposed. 

Clinical Signs
Horses with PPID may show a variety of subtle and advanced signs, including: 
•    Hair coat abnormalities
•    Muscle wasting
•    Laminitis
•    Increased drinking and urination
•    Frequent infections
•    Insulin resistance
•    Delayed wound healing

Diagnosis
Diagnosis involves a combination of clinical evaluation and laboratory testing. Veterinarians assess the horse’s history, physical signs, and may perform blood tests such as resting ACTH and insulin levels to confirm PPID and evaluate insulin dysregulation. Early detection is challenging because initial signs can be subtle. 

Treatment and Management
While PPID cannot be cured, it can be managed effectively:
•    Medication
•    Diet and exercise
•    Hoof care
•    Monitoring and veterinary care 

Prognosis
With proper care, horses with Cushing’s disease can live comfortable, happy lives. Early recognition and consistent management of symptoms, diet, and medication are key to maintaining quality of life. Cushing’s disease is a progressive condition, so ongoing monitoring and adjustments in treatment are necessary to address changes in the horse’s health over time.