Cushings Disease

‘Cushings’(also called Hyperadrenocorticism) is a disease of the endocrine system. It is caused by an abnormality of the pituitary gland, at the base of the brain, which makes the body produce excessive amounts of cortisol – the body’s natural steroid hormone.

Its effects can be seen throughout the body. You may have noticed your horse having:

• Increased thirst
• Increased appetite
• Increased urination
• Pot bellied appearance
• Loss of topline muscle.
• A thick wavy hair coat in the summer – failure to shed its winter coat.
• Chronic laminitis.
• Lethargy

• Immunosuppression that could cause your horse to be prone to other diseases especially skin diseases like rain scald.

• Laminitis. Signs include:
  • Lameness
  • Heat in the feet
  • Increased digital pulses in the feet
  • Reluctant or hesitant gait ("walking on eggshells")
  • A "sawhorse stance," with the front feet stretched out in front to alleviate pressure on the toes and the hind feet "camped out" or positioned further back than normal to bear more weight.
  • Rings in hoof wall that become wider as they are followed from toe to heel
  • Dropped soles or flat feet

There are a number of treatments available for the treatment of Cushing’s disease.

Your vet will decide which is the best treatment for your horse but the principle behind each treatment is very similar. Each treatment is lifelong.

Within the brain a substance called Dopamine prevents overproduction of hormones. Serotonin is another naturally occurring substance, which has the opposite effect. So, to treat your horse you can either use a drug which mimics dopamine (Bromocriptine or more commonly used, Pergolide) or a drug which blocks the effect of Serotonin (Cyproheptidine).

Trilostane, a drug that blocks cortisol, is another alternative, which is about to be licensed in the UK. Ask your vet for further details.

The increase in cortisol is similar to the effects of stress, so decreasing the stress experienced by your horse will help. This can be done by:

• Sticking to a strict routine
• Provide a safe comfortable, quiet haven for the horse.
• Avoiding turnout with aggressive horses.
• Keeping feed and water conveniently located.
• Clipping the horse in warm weather and using rugs when cold.
• Keep the horse well groomed to minimise skin disease.
• Inspect the hooves daily, keep in good shape, and monitor for signs of laminitis (see above).
• Minimise contact with new horses.
• Immunise as necessary.
• Worm regularly.
• Check dental health.
• Provide a high quality, easily digestible diet.

Treatment is lifelong, as is management. This condition cannot be cured but horses can continue in comfort for many years.

Laminitis is the most serious complication.

If you require further information on Cushings Disease, contact your vet.

Top of page