Monitoring Equine Cushings Treatment: ACTH and Welfare

Effective monitoring of PPID treatment in horses using ACTH measurements ensures optimal pergolide dosing and prevents the welfare consequences of under-treatment.

Key Facts

Pituitary pars intermedia dysfunction (PPID/Equine Cushings) affects approximately 15-21% of horses over 15
Pergolide (Prascend) is the only licensed treatment - it reduces ACTH secretion from the pars intermedia
Monitoring treatment adequacy requires measuring ACTH levels, not just clinical signs
Target ACTH should fall within the seasonal reference range for the testing laboratory
Autumn ACTH surge (August-October) requires dose adjustment in many horses - pre-autumn monitoring recommended
Under-treated horses remain at risk of laminitis, immunosuppression, and abnormal fat deposits
Clinical improvement may be evident before ACTH normalizes - biochemical monitoring guides dosing adjustments

Welfare Considerations

PPID causes chronic suffering including laminitis, abnormal fat redistribution, coat problems, muscle wasting, and recurrent infections. Effective treatment with appropriately dosed pergolide substantially reduces this suffering. However, treating without monitoring creates false confidence - clinical improvement may mask persistent hormonal dysregulation that maintains laminitis risk. ACTH-guided dosing adjustments, especially pre-autumn, represent the welfare-positive approach to PPID management.

What You Can Do

Test ACTH levels in horses on pergolide treatment at least annually - ideally spring and pre-autumn
Increase pergolide dose in advance of the autumn ACTH surge based on monitoring results
Continue pergolide for life once PPID is confirmed - the disease is not curable
Monitor laminitis risk indicators closely even in treated PPID horses during high-risk periods
Discuss PPID testing of any horse over 10 showing subtle coat, weight, or laminitis changes