FDA Approves First Generic Pergolide Tablets for Equine Cushing Disease Treatment
Key Insights
The FDA has approved Zygolide (search) (pergolide tablets (search)) by Dechra (search) as the first bioequivalent generic option for treating pituitary pars intermedia dysfunction (search) (PPID (search)) in horses, also known as equine Cushing disease (search).
PPID (search) affects approximately 21% of horses aged 15 and older, with prevalence increasing to 30% in horses over 30 years old, making it one of the most common endocrine disorders in aging horses.
The new generic medication features enhanced design elements including 360-degree scoring for easy splitting, peppermint flavoring, and cost-effective pricing to improve accessibility for horse owners and caregivers.
The FDA has approved pergolide tablets (search) (Zygolide (search); Dechra (search)) as the first bioequivalent generic option for controlling clinical signs associated with pituitary pars intermedia dysfunction (search) (PPID (search)) in horses, also known as equine Cushing disease (search). This approval expands access to an essential therapy for one of the most common endocrine disorders affecting aging horses.
Disease Impact and Prevalence
PPID (search) affects approximately 21% of horses aged 15 and older, with prevalence increasing to 30% in horses over 30 years old. Researchers estimate that approximately 20 to 33% of all horses develop PPID by the age of 20. According to the UC Davis Center School of Veterinary Medicine (search)'s Center for Equine Health, the condition typically occurs in horses older than 15 years, though cases have been documented in horses as young as 7 years of age.
PPID (search) is an age-related endocrine disorder characterized by the degeneration of neurons that affect the production and regulation of hormones, including adrenocorticotrophic hormone (search) (ACTH). Common clinical signs include a long, curly hair coat, delayed shedding, muscle loss, polydipsia, polyuria, lethargy, and laminitis (search). Some horses may also exhibit a rounded abdomen, exercise intolerance, abnormal sweating, and fat deposits above the eyes and on the top of the neck and tailhead. Additionally, affected horses face higher risk of chronic infection and abscesses, decreased wound healing, and higher parasite burdens.
Enhanced Treatment Features
Zygolide (search) offers several enhanced features designed to improve the treatment experience for both horses and their caretakers. The tablet is designed with a manageable size and shape, featuring 360-degree scoring on all sides to make it simple to split as needed. The medication comes in a peppermint flavor to provide an enhanced experience during administration.
"The FDA approval of Zygolide (search) brings to market a high-quality, cost-effective option to help make the management of PPID (search) more accessible," said Dr. Greg Schmid, Equine Medical Affairs Lead at Dechra (search). "This therapy provides another option for horses living with the condition, including a pill structure with 360-degree scoring on all sides and a peppermint flavor profile, helping to reduce stress for both horses and their caretakers."
Safety Profile and Availability
The medication is administered orally and has not been evaluated in breeding, pregnant, or lactating horses. Adverse effects include loss of appetite, weight loss, lack of energy, and behavioral changes. According to Dechra (search), most cases of appetite loss are mild, though a temporary reduction in dose may be necessary in severe cases. Pergolide tablets (search) is contraindicated in horses with hypersensitivity to pergolide mesylate or other ergot derivatives.
Important safety considerations include that tablets should not be crushed due to the potential for increased human exposure, and pregnant or lactating women should wear gloves when administering this product. The medication must be kept in a secure location out of reach of dogs, cats, and other animals to prevent accidental ingestion or overdose, as adverse reactions may occur if animals other than horses ingest the tablets.
Zygolide (search) is now available through veterinarians beginning January 2026 and can be purchased with a prescription from major online pharmacies nationwide. As a generic option, Zygolide offers cost relief to horse owners and caretakers, particularly for horses that receive higher doses of treatments for PPID (search). Currently, the medication is only available in the United States.