The TRH (thyrotropin-releasing hormone) stimulation test is a dynamic test that's recommended for the diagnosis of PPID in horses with equivocal baseline ACTH results.
In the most recent recommendations released by the Equine Endocrinology Group (whose members are experts in equine endocrinology), the TRH test is considered an appropriate first-line test — especially in horses with mild or early clinical signs and in younger horses that are suspected to be suffering from PPID.
Early diagnosis of PPID is desirable because treatment with pergolide (Prascend®) can be initiated earlier before more severe clinical signs associated with PPID develop.
To refer a horse for a TRH stimulation test, please call the WCVM Large Animal Clinic (306-966-7178). Click here to view additional PPID resources (including a recent WCVM EquineED Talk session) for your clients.