Learn about PPID in horses

Pituitary pars intermedia dysfunction (PPID), also referred to as equine Cushing’s disease, is a progressive neurodegenerative disorder in horses. In horses with PPID, the pituitary gland can’t keep bodily functions in a healthy working state, resulting in a variety of clinical signs. PPID is also associated with several serious conditions including laminitis, secondary infections and insulin dysregulation.

Identifying PPID in Horses
Explore Clinical Signs

Signs of PPID can be subtle, but the disease can be serious. Knowing what to look for can lead to an early diagnosis.

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  • Change in attitude/lethargy

  • Decreased performance

  • Delayed hair coat shedding

  • Loss of topline muscle

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  • Abnormal sweating

  • Recurrent infections

  • Laminitis

  • Dry eye/recurrent corneal ulcers

See All the Signs
3 Main Components for Identifying PPID

Diagnosing PPID requires a comprehensive approach. The three main components are: collecting a comprehensive patient history, conducting a detailed physical examination and submitting plasma samples for testing. Because the illness may initially present through a collection of relatively subtle clinical signs, PPID is easier to diagnose when using all information available. 

Step 1
Patient History

The veterinarian and the horse owner should talk about the horse’s history, both clinical and behavioral. This can help the veterinarian uncover subtle behaviors that take more time to notice like changes in attitude and lethargy, weight loss, or decreased athletic performance.


TIP: Our checklist of clinical signs can help horse owners prepare to talk to their veterinarian.

Clinical Signs Checklist
Step 2
Physical Examination

As the veterinarian examines the horse, they will look for clinical signs of PPID such as delayed coat shedding, abnormal sweating and regional or generalized muscle loss.

Step 3
Blood Testing

If one or more clinical signs are present, it’s time to test. Your veterinarian will pull blood to measure resting adrenocorticotropic hormone (ACTH) levels (alongside insulin and glucose). During certain months, a thyrotropin releasing hormone (TRH) stimulation test is also recommended for horses with early PPID or advanced horses with a normal resting ACTH.

Developing a 360° Care Plan From Hoof to Teeth

To properly manage PPID, it is important horse owners work closely with their veterinarians to build a plan. Concurrent illnesses such as insulin dysregulation or concurrent equine metabolic syndrome (EMS) can impact the PPID management plan.

Managing PPID
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Pharmaceutical treatment

Pergolide is the drug of choice for PPID in horses, and PRASCEND is the most proven treatment available to control the clinical signs associated with PPID in horses.1 PRASCEND tablets should not be crushed due to the potential for increased human exposure.

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Proper Diet and Adequate Exercise

Talk to your veterinarian to create a diet and exercise program specific for your horse based on body condition score, clinical signs present and laboratory results.

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Proper Vaccination

It was recommended to consider horses with advanced PPID for twice yearly vaccination for West Nile virus in endemic areas.2

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Regular Care from Hoof to Teeth

Maintain proper hoof care, and communicate any abnormal observations to your veterinarian and farrier. Regular dental exams (teeth floating as needed).

Regular Deworming

Horses with PPID also have been shown to have higher fecal strongyle egg counts, suggesting that they are more likely to shed eggs in higher numbers.3

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Body Clipping, If Necessary

Many horses with PPID fail to shed out completely in the spring or, at the very least, shed later than herd or stable mates.

Controlling the Clinical Signs of PPID with PRASCEND

Because PPID is a chronic disease, afflicted horses need daily, lifelong medical treatment. The good news is: There is a solution that can help control the clinical signs associated with PPID. PRASCEND can help control the clinical signs of PPID in horses and decrease the risk of other illnesses that may be associated with PPID.4  Treatment with PRASCEND may cause loss of appetite. Most cases are mild.

Understanding Endocrine Disorders in Horses

The Equine Endocrinology Group (EEG) is a group of clinicians and researchers working to advance our understanding of endocrine disorders in horses. Together, these key opinion leaders advise veterinarians, specialists, research scientists, and the public on equine endocrine disorders—with the mission of improving recognition, diagnosis and management.

2021 EEG PPID Recommendations

IMPORTANT SAFETY INFORMATION: PRASCEND is for use in horses only. PRASCEND has not been evaluated in breeding, pregnant, or lactating horses. Treatment with PRASCEND may cause loss of appetite. Most cases are mild. If severe, a temporary dose reduction may be necessary. Weight loss, lack of energy, and behavioral changes also may be observed. PRASCEND is contraindicated in horses with hypersensitivity to pergolide mesylate or other ergot derivatives. Not for use in humans. Do not ingest the product. PRASCEND tablets should not be crushed due to the potential for increased human exposure. Pergolide, like other ergot derivatives, may cause emesis, dizziness, lethargy or low blood pressure. Pregnant or lactating women should wear gloves when administering this product. Store this product separately away from human medicinal products and handle this product with care to avoid accidental ingestion. Keep PRASCEND in a secure location out of reach of dogs, cats, and other animals to prevent accidental ingestion or overdose. Dogs have eaten PRASCEND tablets that were placed in food intended for horses or dropped during administration of the tablets to the horses. Adverse reactions may occur if animals other than horses ingest PRASCEND tablets. Refer to the package insert for complete product information.