Cushing's syndrome in horses-incurable but well under control?

Equine Cushing's Syndrome, or ECS for short, has become a source of discomfort for many horse owners. Among equine diseases, Cushing's is unfortunately one of the most common "diseases of affluence". In fact, this term is relevant, because in real terms the rather meagre horse life of the past can no longer be compared to that of today.

We would like to explain to you in detail exactly what triggers the disease and what to do when Cushing's syndrome is diagnosed in a horse. Expert knowledge can prevent the disease, be a good support and at best help.

Definiton of Cushing including causes

In addition to ECS, the term PPID (Pituitary Pars Intermedia Dysfunction) is now often used. The term comes from English and indicates that a pathologically enlarged pituitary gland plays an important role. Together with the adrenal cortex, hormones are produced in excess in the body. This supply is simply too much for the metabolism.

This means that the brain normally sends out dopamine substances. In Cushing's syndrome, however, these partially die off. This is usually the trigger for the brain gland to get out of control in its activity.

The gland then releases a huge amount of substances to the adrenal cortex, which continues to produce cortisol (which is actually released during stress!) with messenger substances and hormones. There, the cortisol ensures an increased blood sugar level. The horse's organism is therefore in a constant state of alert. This extensive misproduction weakens the animal's defences in the long run and therefore triggers many symptoms of ECS.

Another cause of this disease can be permanent medication with cortisone. A rapid progression of the cushioning is often clearly noticeable here. Consequently, a severe metabolic disorder develops in the horse.

Feeding that is too high in sugar and energy and stress are also questioned as reasons for the condition.

Age-related, mostly older animals (from 15) have to struggle with PPID. Almost every 5th horse is affected. Nevertheless, there are more and more younger horses that already suffer from it.

Symptoms of Cushing's syndrome

-Rapid sweating (disturbed thermoregulation) and rapid fatigue

-Increased water intake and urination (increased liver and kidney values!)

-the animal's activity decreases up to apathy

-Weight Loss

-fat redistribution(e.g. visible fat pads on the ridge, croup or above the eyes)

-Muscle loss on the horse strongly visible on the back

-the belly hangs, often low back

-possible insulin resistance

-impaired fertility

-poor hoof horn

-diseased animal is prone to hoof ulcers

-Laminitis (an issue in 50 - 80% of all horses with the disease)

-Dental diseases or cushing-related ulcers in the mouth

-Loss of appetite

-Wounds heal poorly

-Disturbed coat change in horses (long, shaggy, curly or wavy hair = hirsutism)

-possible degeneration of bone, muscle and connective tissue

How is Cushing's syndrome diagnosed?

The vet will of course ask and look for these symptoms. To confirm the whole diagnosis, a blood test is appropriate. Here the ACTH level can be determined. This determination is also very important to distinguish the EMS disease, which runs in a similar way.

Values of >50 pg/ml are critical. If the value is above >100 pg/ml, this undoubtedly indicates Cushing's syndrome in the horse.

A TRH stimulation test can also provide information as to whether the animal is ill. Here, the cortisol value is determined. Then the TRH hormone is added and measured again. If the value increases significantly within half an hour, this indicates ECS. In combination with the dexamethasone test, this is a very reliable way of detecting ECS.

Therapy options for a Cushing's horse

Unfortunately, this serious metabolic disorder in horses cannot be cured. But this does not have to mean the worst. Thanks to a pergolide preparation prescribed by the veterinarian and simultaneous, needs-based administration of certain micronutrients as well as bioactive substances, it is still possible to maintain functioning metabolic activities. The whole thing is then called "palliative therapy". It now accompanies the animal virtually until the end of its life.

Possible procedure: 

-A pergolide drug (stimulates the release of dopamine) is prescribed.

-Monk's pepper (is also said to positively support ECS horses)


-bioactive substances

-increased need for antioxidants (vitamins)

It also becomes apparent:

Dietary measures are necessary!

Exemplary Feeding of a Cushing's horse

Basic feed:

High quality hay and forage straw are important for a healthy intestinal function. For animals at risk of laminitis, it makes sense to water the hay. But beware: the nutrients also disappear in the process!

If the horse is too thin, high-quality protein (soya meal) and amino acids can be added.

Energy feed:

Grain is deliberately avoided. No molasses muesli! They only trigger a high glucose and insulin reaction. Unmelassed beet pulp and oils (e.g. linseed oil) are better.

Fruit, carrots and too much grass are not ideal. A lot of glucose is hidden here.

Mineral feed:

The increased need for micronutrients can be determined by the vet. This supplementary feeding is very important to cope with nutrient imbalances. It supports all processes in the body and can actually slow down the progression of Cushing's syndrome in horses.

Bioactive plant compounds are defence-boosting and are just as important a part of the diet.


Follow-up examinations and also regular monitoring checks make visible what is still lacking. This is the only way to ensure the exact dosage of medicine, minerals, nutrients and nutrition. Your vet will certainly be able to give you advice and support.

Can you prevent Cushing's disease in horses?

Certainly, species-appropriate husbandry, social contact, sufficient exercise and, above all, feeding that meets the horse's needs is the best prevention for ECS. Of course, this also applies to all other equine diseases.

However, overweight plays a decisive role and should be avoided. Exercise incentives in an open or active stable, which sometimes also have digital feed monitoring, are recommended. In general, always keep exercise and feeding in balance. This is already "half the battle" and an important health formula. 

Still have a horse that has Cushing's -what now?

Absolute to do: Keep an active health management.


-Adhere to daily medication (a pillbox with marked days of the week is ideal for owner/riding partner).

-Do not miss the vet's check-ups

-continue regular dental and hoof care

-exercise adapted to the degree of illness

-an individual ration calculation for feeding is desirable

-If necessary, shear the horse in spring/summer.

- Ensure good, absorbent bedding in case of a strong urge to urinate.

This way your partner will surely get better quickly. In fact, there is a really good prognosis with early detection. All the best for you!