Cushing’s Syndrome in Dogs and Cats: Symptoms, Warning Signs and What to Do

 

Cushing’s Syndrome in Dogs and Cats: Symptoms, Warning Signs and What to Do

By Dr Duncan Houston

Cushing’s syndrome often develops so gradually that the first signs are mistaken for normal ageing.

A dog may begin drinking more, waking at night to urinate, panting indoors and constantly searching for food. Their abdomen may become rounded while the muscles over their back and legs quietly shrink.

Cats usually present differently. Feline Cushing’s syndrome is rare, but it can be severe. Many affected cats are first investigated because their diabetes is difficult to regulate, they are losing muscle, their abdomen is enlarged or their skin has become frighteningly thin and fragile.

One sign alone rarely confirms Cushing’s syndrome. The pattern, progression and combination of symptoms are what make the diagnosis more likely.

Quick Answer

The most common symptoms of Cushing’s syndrome in dogs are increased thirst and urination, increased appetite, excessive panting, a pot-bellied appearance, muscle weakness and characteristic skin or coat changes.

In cats, important warning signs include difficult-to-regulate diabetes, weight loss, muscle wasting, abdominal enlargement, poor hair regrowth and very thin skin that may tear after minor handling. Cushing’s syndrome itself usually develops slowly, but breathing difficulty, collapse, seizures, sudden blindness, severe weakness, vomiting, diarrhoea or refusal to eat can indicate a serious complication and require urgent veterinary care.

What Is Cushing’s Syndrome?

Cushing’s syndrome is the collection of clinical signs caused by prolonged exposure to excessive glucocorticoid activity, most importantly cortisol.

The condition is also called:

• Hypercortisolism

• Hyperadrenocorticism

• Cushing’s syndrome

The terminology can become confusing. Cushing’s disease technically refers specifically to the pituitary-dependent form, while Cushing’s syndrome includes all causes of excessive glucocorticoid activity.

Cortisol is essential in normal amounts. It helps regulate:

• Blood glucose

• Blood pressure

• Metabolism

• Inflammation

• Immune responses

• The body’s reaction to stress

Problems develop when the tissues are exposed to excessive glucocorticoid activity for months or years.

What Causes Cushing’s Syndrome?

Cushing’s syndrome can be naturally occurring or caused by medication.

Pituitary-dependent Cushing’s syndrome

A tumour or abnormal area within the pituitary gland produces excessive adrenocorticotropic hormone, commonly shortened to ACTH.

ACTH stimulates both adrenal glands to produce excessive cortisol.

Pituitary-dependent disease accounts for the large majority of naturally occurring cases in dogs and also appears to be the most common form in cats.

Adrenal-dependent Cushing’s syndrome

A functional tumour in one adrenal gland produces cortisol independently.

The abnormal gland may be benign or malignant. The opposite adrenal gland often becomes smaller because normal pituitary ACTH production is suppressed.

Adrenal-dependent disease accounts for a minority of naturally occurring canine and feline cases.

Iatrogenic Cushing’s syndrome

Iatrogenic Cushing’s syndrome is caused by chronic exposure to prescribed glucocorticoid medication.

Potential sources include:

• Prednisone or prednisolone tablets

• Repeated steroid injections

• Steroid-containing ear medication

• Steroid eye drops

• Topical skin creams or sprays

• Inhaled corticosteroids

• Some progestin medications

The amount absorbed from ear, eye and skin products may be clinically important, particularly when potent medication is used repeatedly or over a large area. A complete medication history is therefore essential.

Do not abruptly stop long-term steroid treatment. Chronic glucocorticoid administration can suppress natural adrenal function, and sudden withdrawal may cause dangerous cortisol deficiency. The medication must usually be tapered under veterinary direction.

How Does Excess Cortisol Cause So Many Different Symptoms?

Cortisol affects almost every organ system.

Persistent excess can:

• Increase thirst and urine production

• Increase appetite

• Raise blood glucose

• Promote insulin resistance

• Break down muscle protein

• Redistribute body fat

• Weaken the abdominal muscles

• Thin the skin

• Interrupt normal hair growth

• Delay wound healing

• Suppress immune function

• Increase susceptibility to infection

• Alter blood pressure and blood clotting

• Affect the liver, gallbladder and urinary tract

This explains why Cushing’s syndrome can initially look like several unrelated problems occurring at once.

Symptoms of Cushing’s Syndrome in Dogs

The classic canine pattern is a gradually developing combination of thirst, urination, hunger, panting, abdominal enlargement, muscle loss and dermatological change.

Not every dog develops every sign. Early cases may show only two or three subtle abnormalities.

Increased Thirst and Urination

Increased drinking and urination are among the most common and noticeable signs.

Owners may report that their dog:

• Empties the water bowl much faster

• Starts drinking from toilets, puddles or showers

• Wakes during the night to drink

• Needs more frequent walks

• Produces unusually large volumes of urine

• Begins urinating indoors

• Develops overnight accidents

• Appears to have worsening urinary incontinence

The urine is often dilute because excessive cortisol affects normal water balance and kidney function.

Do not restrict access to water. A dog producing excessive urine must be allowed to replace that fluid while the underlying cause is investigated.

Increased Appetite

Dogs with Cushing’s syndrome commonly become unusually hungry.

You may notice:

• Constant begging

• Searching benches and cupboards

• Stealing food

• Raiding rubbish

• Eating another animal’s meals

• Waking owners for food

• Appearing hungry immediately after eating

This can be mistaken for good health, particularly in an older dog. A new ravenous appetite combined with excessive thirst, panting or abdominal enlargement is much more concerning than hunger alone.

Excessive Panting

A dog with Cushing’s syndrome may pant:

• While resting

• During cool weather

• Overnight

• After very little activity

• Without appearing hot or anxious

Panting can be related to hormonal effects, abdominal enlargement, reduced respiratory muscle strength, obesity and altered temperature regulation.

Panting is not specific to Cushing’s syndrome. Pain, heat, anxiety, heart disease, lung disease, anaemia and medication can cause similar changes.

Breathing that is genuinely laboured, associated with blue or pale gums, or accompanied by collapse is not routine Cushing’s panting and must be treated as an emergency.

Pot-Bellied Appearance

Many affected dogs develop a rounded or pendulous abdomen.

This appearance commonly reflects a combination of:

• Weakening of the abdominal muscles

• Enlargement of the liver

• Redistribution of body fat

• Stretching of the abdominal wall

The rest of the body may simultaneously become thinner. A dog can therefore appear overweight around the abdomen while losing muscle over the spine, hips and legs.

A suddenly swollen or painful abdomen is not the typical slow pot-bellied change of Cushing’s syndrome. Acute distension, vomiting, collapse or abdominal pain requires urgent examination.

Muscle Weakness and Wasting

Chronic cortisol excess promotes the breakdown of muscle protein.

Possible signs include:

• Difficulty climbing stairs

• Reluctance to jump into the car

• Trouble rising from the floor

• Shorter walks

• Trembling legs

• Loss of muscle over the spine and hips

• A narrower appearance through the thighs

• Reduced stamina

• General lethargy

The pot-bellied appearance is partly caused by this loss of abdominal muscle tone.

Severe weakness can also be caused by diabetes, electrolyte abnormalities, infection, blood clots or another concurrent illness, so it should not automatically be blamed on the endocrine disease.

Skin and Coat Changes in Dogs

Canine Cushing’s syndrome can create a characteristic endocrine skin pattern.

Possible changes include:

• Symmetrical hair thinning or hair loss

• Hair loss affecting the trunk while the head and lower legs remain relatively spared

• Hair failing to regrow after clipping

• Thin skin

• Visible superficial blood vessels

• Darkening of the skin

• Blackheads or comedones

• Scaling

• Easy bruising

• Slow wound healing

• Recurrent bacterial skin infections

• Recurrent yeast infections

The primary endocrine hair loss is often not very itchy. Marked itching suggests secondary infection, parasites, allergy or another skin condition may also be present.

Calcinosis cutis

Calcinosis cutis occurs when calcium salts are deposited within damaged skin.

It may look or feel like:

• Firm gritty plaques

• White or yellow material beneath the skin

• Hard irregular bumps

• Crusted or ulcerated areas

• Painful inflamed skin

• Mineralised lesions along the back, neck, abdomen or groin

This finding is strongly associated with chronic glucocorticoid excess, although it is not present in every affected dog.

Recurrent Infections

Excess cortisol suppresses immune defences and may make infections less obvious.

Affected dogs have an increased risk of:

• Urinary tract infection

• Skin infection

• Ear infection

• Dental or oral infection

• Respiratory infection

A urinary infection may be present without obvious straining or discomfort. This is why urinalysis and, in appropriate cases, a urine culture form part of the investigation. Dogs with Cushing’s syndrome are also at increased risk of several important comorbidities, including diabetes mellitus, urinary tract infection, hypertension, gallbladder mucocele and thromboembolic disease.

High Blood Pressure

Hypertension may develop in dogs with Cushing’s syndrome.

High blood pressure may cause no visible signs, or it may contribute to:

• Sudden vision loss

• Bleeding within the eye

• Neurological abnormalities

• Kidney damage

• Protein loss through the urine

Blood pressure should therefore be assessed as part of the wider work-up, especially when there are eye, kidney or neurological concerns.

Diabetes Mellitus

Cortisol promotes insulin resistance.

Dogs with both Cushing’s syndrome and diabetes may show:

• Marked thirst and urination

• Weight loss despite hunger

• Persistent high blood glucose

• Glucose in the urine

• Difficulty achieving stable diabetic control

• Recurrent infections

• Cataracts or sudden visual deterioration

Diabetes is more common in dogs with Cushing’s syndrome than in the general canine population, but most diabetic dogs do not automatically have Cushing’s syndrome.

Gallbladder Disease

Dogs with Cushing’s syndrome have an increased association with gallbladder mucocele.

A mucocele may remain silent, or it may cause:

• Reduced appetite

• Vomiting

• Abdominal pain

• Lethargy

• Jaundice

• Fever

• Collapse if the gallbladder ruptures

These are not routine chronic signs of Cushing’s syndrome. They indicate a possible complication that requires urgent investigation.

Blood Clots

Cushing’s syndrome increases the risk of abnormal clot formation.

A pulmonary thromboembolism can cause:

• Sudden rapid breathing

• Marked breathing effort

• Weakness

• Collapse

• Low oxygen levels

• Occasionally coughing blood

• Sudden death

Dogs with hyperadrenocorticism have an increased association with thromboembolic disease, and respiratory abnormalities may also be worsened by muscle weakness and mineralisation within the respiratory system.

Neurological Signs From a Pituitary Mass

Most pituitary tumours causing Cushing’s syndrome are small and primarily produce hormonal signs.

A larger pituitary tumour can compress nearby brain tissue and cause:

• Behaviour or personality changes

• Pacing

• Circling

• Reduced awareness

• Loss of learned behaviour

• Sudden or progressive vision loss

• Seizures

• Head pressing

• Reduced appetite

• Difficulty walking

These signs reflect the physical effect of the pituitary mass rather than cortisol excess alone. They require prompt neurological assessment and advanced imaging may be recommended.

Symptoms of Cushing’s Syndrome in Cats

Cushing’s syndrome is far less common in cats than dogs.

The feline presentation is also different enough that a cat should not be treated as a miniature canine Cushing’s case.

The most important patterns are:

• Diabetes that is difficult to regulate

• Thin and fragile skin

• Abdominal enlargement

• Muscle wasting

• Weight loss

• Poor hair regrowth

• Weakness

• Recurrent infections

Most reported feline cases have pituitary-dependent disease, although adrenal tumours also occur.

Diabetes Mellitus Is a Major Clue in Cats

Most, but not all, cats with Cushing’s syndrome have concurrent diabetes mellitus. The diabetes is often insulin resistant and difficult to regulate.

Possible signs include:

• Increased drinking

• Increased urination

• Increased appetite

• Weight loss

• Weakness

• Glucose in the urine

• Persistently high blood glucose

• Large or frequently changing insulin requirements

• Recurrent diabetic instability

In cats, the excessive thirst, urination and appetite may largely reflect persistent hyperglycaemia rather than cortisol excess by itself.

However, most difficult-to-regulate diabetic cats do not have Cushing’s syndrome. More common causes must be assessed first, including:

• Incorrect insulin administration

• Inappropriate insulin type or dose

• Diet inconsistency

• Infection

• Dental disease

• Obesity

• Acromegaly

• Hyperthyroidism

• Chronic kidney disease

• Pancreatitis

• Medication interference

Cushing’s syndrome becomes more suspicious when poor diabetic control occurs alongside abdominal enlargement, muscle loss, failure of hair regrowth or unusually fragile skin.

Fragile, Thin Skin

Extreme skin fragility is one of the most clinically important signs of feline Cushing’s syndrome.

The skin may appear:

• Thin and translucent

• Dry and papery

• Poorly elastic

• Easily bruised

• Marked by prominent veins

• Sparse or poorly haired

• Slow to heal

Skin may tear during:

• Normal grooming

• Clipping

• Blood collection

• Ultrasound preparation

• Lifting or restraint

• Contact with a cage or carrier

• Scratching

• Routine handling

Up to approximately one-third of reported cats have developed extreme skin fragility. Veterinary teams must handle suspected cats with exceptional care because large wounds can be created by very minor trauma.

A new skin tear should be protected from contamination and assessed promptly. Large wounds, uncontrolled bleeding or exposed deeper tissue may require emergency treatment.

Abdominal Enlargement

Cats may develop a rounded abdomen because of:

• Weak abdominal muscles

• Liver enlargement

• Internal fat deposition

• Reduced muscle support

This can occur at the same time as obvious weight loss over the back and limbs.

The abdomen may therefore look larger even while the cat’s total body condition and muscle mass are deteriorating.

Weight Loss and Muscle Wasting

Weight loss is common in affected cats, particularly when diabetes is present.

Possible signs include:

• Prominent spine or hips

• Reduced muscle over the back

• Thin legs

• Generalised weakness

• Difficulty jumping

• Reduced grooming

• A sagging abdomen despite loss of body mass

Some cats develop a plantigrade stance, walking with the hocks lowered towards the ground. This may reflect diabetic neuropathy, muscle weakness, low potassium or a combination of abnormalities.

Hair and Coat Changes in Cats

Possible changes include:

• Bilaterally symmetrical hair loss

• Patchy alopecia

• Sparse, brittle hair

• An unkempt coat

• Scaling or seborrhoea

• Failure of clipped hair to regrow

• Comedones on the abdomen

• Skin infections

• Nail-bed infections

Hair may remain absent for months after routine clipping. A failure to regrow hair is not specific to Cushing’s syndrome, but it becomes more meaningful when combined with diabetes, muscle wasting or fragile skin.

Recurrent Infections in Cats

Immune suppression can increase susceptibility to infection affecting:

• Skin

• Nail beds

• Urinary tract

• Respiratory tract

• Gastrointestinal tract

• Oral and dental tissues

An affected cat may first be presented because of an infection rather than the endocrine disorder itself.

Other Possible Signs in Cats

Less common findings include:

• Lethargy

• Generalised weakness

• Hypertension

• Sudden vision changes from hypertensive eye disease

• Neurological signs from a large pituitary tumour

• Vomiting or diarrhoea

• Reduced appetite

• A palpable adrenal mass

• Low potassium

Unlike dogs, elevations in alkaline phosphatase are much less predictable because cats do not have the same glucocorticoid-induced alkaline phosphatase isoenzyme. Normal canine-style liver enzyme patterns therefore do not rule feline disease in or out.

Dogs and Cats Do Not Show Cushing’s Syndrome the Same Way

Feature	Dogs	Cats
Overall frequency	Relatively common endocrine disorder	Rare
Typical early clue	Increased thirst, urination, appetite and panting	Difficult-to-regulate diabetes
Abdominal change	Pot-bellied appearance is common	Abdominal enlargement is also common
Muscle change	Weakness and wasting	Weight loss, wasting and weakness
Skin change	Symmetrical hair loss, thin skin, poor regrowth and infections	Extreme skin fragility, tears and poor hair regrowth
Diabetes	Possible and more common than in unaffected dogs	Present in the majority of reported cases
Alkaline phosphatase	Often increased	May remain normal
ACTH stimulation testing	Useful in selected diagnostic situations	Poor sensitivity as an initial diagnostic test
Overall management	Frequently managed successfully with medication	Often more complicated because of diabetes and skin fragility

How Worried Should You Be?

Risk level	What it may look like	What to do
Lower immediate risk	Gradual thirst, increased appetite, panting, pot belly or slow coat changes while the pet remains bright and comfortable	Arrange a veterinary examination within one to two weeks
Moderate concern	Indoor urination, marked muscle loss, recurrent infections, poor hair regrowth or difficult diabetic control	Book a veterinary examination within the next few days
High concern	Significant weakness, a large feline skin tear, rapidly worsening diabetes, sudden vision changes, severe lethargy or refusal to eat	Seek same-day veterinary care
Critical	Breathing difficulty, collapse, seizures, severe abdominal pain, repeated vomiting, diabetic ketoacidosis signs or profound weakness	Go to an emergency veterinary hospital immediately

Cushing’s syndrome is usually chronic rather than suddenly catastrophic. Acute deterioration generally means a complication, another illness or excessive suppression from treatment has developed.

When Is Cushing’s Syndrome an Emergency?

Go to an emergency veterinary hospital immediately if your dog or cat develops:

• Open-mouth or severely laboured breathing

• Blue, grey or very pale gums

• Sudden collapse

• Seizures

• Sudden blindness

• Severe disorientation or circling

• Uncontrolled bleeding

• A large traumatic skin tear

• Severe abdominal pain or distension

• Repeated vomiting with weakness

• Inability to stand

• Rapid deterioration over several hours

These signs may indicate:

• Pulmonary thromboembolism

• Diabetic ketoacidosis

• Gallbladder rupture

• Severe infection

• Hypertensive crisis

• Pituitary macroadenoma

• Electrolyte disturbance

• Internal bleeding

• Another unrelated emergency

Vomiting, diarrhoea and poor appetite in dogs

Naturally occurring canine Cushing’s syndrome usually causes increased appetite rather than refusal to eat.

Vomiting, diarrhoea and anorexia are not typical direct signs of uncomplicated canine hypercortisolism. They should prompt investigation for another illness or an associated complication rather than being dismissed as “just the Cushing’s”.

Warning signs in pets receiving trilostane

A dog receiving trilostane may become dangerously cortisol-deficient if treatment suppresses adrenal function too strongly.

If a treated dog develops:

• Poor appetite

• Vomiting

• Diarrhoea

• Marked lethargy

• Weakness

• Trembling

• Collapse

do not give the next trilostane dose and contact the treating veterinarian urgently. Severe signs require emergency care.

What Else Can Look Like Cushing’s Syndrome?

Many common diseases can produce one or more similar signs.

Conditions That Can Mimic Cushing’s Syndrome in Dogs

Diabetes mellitus

Diabetes causes increased thirst, increased urination, hunger and weight loss. Blood and urine glucose testing helps distinguish it.

Chronic kidney disease

Kidney disease can cause increased drinking and urination, weight loss and weakness, but appetite is often reduced rather than dramatically increased.

Liver disease

Liver enlargement, increased liver enzymes, abdominal distension and excessive thirst can resemble Cushing’s syndrome.

Urinary tract infection

A urinary infection may cause accidents, frequent urination or increased drinking and can also occur as a complication of Cushing’s syndrome.

Hypothyroidism

Hypothyroidism may cause hair loss, weight gain, reduced energy and recurrent skin disease. It does not usually cause the classic combination of marked thirst, urination and increased appetite.

Obesity and age-related muscle loss

An older overweight dog may develop abdominal enlargement and reduced mobility without having Cushing’s syndrome.

Chronic steroid administration

Prescribed steroids can produce the same outward signs while suppressing the pet’s natural adrenal function.

Primary skin disease

Allergy, parasites, bacterial infection, fungal disease and other endocrine disorders can cause hair loss or darkened skin.

Conditions That Can Mimic Cushing’s Syndrome in Cats

Important alternatives include:

• Diabetes mellitus without Cushing’s syndrome

• Acromegaly

• Hyperthyroidism

• Chronic kidney disease

• Liver disease

• Chronic steroid or progestin exposure

• Severe chronic illness

• Protein malnutrition

• Other causes of feline skin fragility

• Pituitary or adrenal disease producing different hormones

The clue is rarely one abnormal feature. It is the combination of endocrine signs with characteristic physical changes.

How Do Vets Diagnose Cushing’s Syndrome?

Cushing’s syndrome cannot be diagnosed from appearance alone.

The diagnosis requires:

1. Compatible clinical signs

2. Supportive routine laboratory findings

3. Appropriate endocrine testing

4. Differentiation between pituitary, adrenal and medication-related disease where necessary

No available endocrine test is perfect. Testing animals without compatible clinical signs increases the risk of false-positive results and overdiagnosis.

Initial Tests

The initial investigation commonly includes:

• Complete blood count

• Serum biochemistry

• Urinalysis

• Urine specific gravity

• Urine culture where indicated

• Blood-pressure measurement

• Urine protein-to-creatinine ratio

• Blood glucose

• Assessment for concurrent disease

The veterinarian should also review every medication, including ear drops, eye drops, injections and topical products.

Testing Dogs

Low-dose dexamethasone suppression test

The low-dose dexamethasone suppression test, or LDDST, is commonly recommended as the initial endocrine test in a dog with compatible clinical signs and no major uncontrolled concurrent illness.

It may also help identify a pituitary-dependent pattern in some dogs.

ACTH stimulation test

The ACTH stimulation test may be useful when:

• Iatrogenic Cushing’s syndrome is suspected

• Certain concurrent illnesses are present

• LDDST results are inconclusive

• Treatment monitoring or cortisol deficiency is being assessed

Its sensitivity for naturally occurring disease, particularly adrenal-dependent disease, is lower than that of the LDDST.

Urine cortisol-to-creatinine ratio

A urine cortisol-to-creatinine ratio, or UCCR, is highly sensitive but poorly specific.

A normal home-collected result makes Cushing’s syndrome less likely. An increased result does not confirm the disease because stress and many illnesses can increase urinary cortisol.

Testing Cats

Feline endocrine testing differs from canine testing.

Low-dose dexamethasone suppression test

The feline LDDST uses a higher dexamethasone dose than the canine protocol.

It is generally considered the most reliable initial confirmatory test for feline Cushing’s syndrome when the clinical picture is compatible.

Urine cortisol-to-creatinine ratio

At least two morning urine samples collected at home may be used as an initial screening test.

A negative result makes feline Cushing’s syndrome less likely. A positive result requires follow-up testing because stress and other disease can increase the result.

ACTH stimulation test

The ACTH stimulation test has poor sensitivity for naturally occurring feline Cushing’s syndrome and is not recommended as the main initial screening test.

Should a Sick Pet Be Tested Immediately?

Not always.

Acute illness can activate the stress response and produce false-positive endocrine results, particularly with the LDDST.

When a dog is acutely vomiting, experiencing diarrhoea, refusing food or seriously unwell, the immediate illness should be diagnosed and treated first. Where possible, AAHA guidance recommends waiting approximately two to four weeks after recovery before testing for Cushing’s syndrome.

The exception is when a specialist decides that the suspected endocrine disease must be investigated sooner because it is directly affecting management of the acute condition.

How Do Vets Determine the Cause?

After Cushing’s syndrome has been confirmed, further investigation may include:

• Endogenous ACTH measurement

• Abdominal ultrasound

• Adrenal CT

• Pituitary CT or MRI

• Interpretation of the LDDST pattern

• Additional endocrine testing

• Assessment for an adrenal mass

• Neurological imaging when a pituitary macroadenoma is suspected

Imaging should usually support and differentiate a confirmed endocrine diagnosis rather than replace hormonal testing.

An adrenal nodule discovered incidentally in an older pet does not automatically mean it is producing cortisol.

What Should You Do Right Now?

1. Measure water intake

Record how much water is added to the bowl over 24 hours.

Account for:

• Multiple bowls

• Other pets sharing the water

• Water added to food

• Toilet, shower or outdoor drinking

Repeat the measurement for two or three days if practical.

Do not deliberately restrict water.

2. Record urination changes

Write down:

• New indoor accidents

• Night-time urination

• Increased walk frequency

• Urine volume

• Worsened incontinence

• Straining or discomfort

• Blood in the urine

Large-volume urination suggests a different problem from repeatedly passing tiny amounts.

3. Track appetite

Record whether your pet is:

• Constantly hungry

• Stealing food

• Losing weight despite eating

• Becoming less interested in food

• Vomiting

• Eating inconsistently

Poor appetite is particularly important because it is not the expected classic canine pattern.

4. Photograph physical changes

Take clear photographs of:

• The abdomen

• Coat thinning

• Darkened skin

• Blackheads

• Areas failing to regrow

• Muscle loss over the back and hips

• Any feline skin wounds

Repeat the photographs monthly from similar angles.

5. Count panting episodes

Note whether panting occurs:

• During sleep or rest

• In cool rooms

• Overnight

• After minimal activity

• During stress

• After medication

Record any true breathing effort separately. Panting and laboured breathing are not the same thing.

6. List every medication

Include:

• Tablets

• Injections

• Ear drops

• Eye drops

• Skin creams

• Sprays

• Inhalers

• Supplements

• Previous long-acting injections

Write down how often each product is used and for how long.

7. Arrange a veterinary appointment

A stable pet with gradual signs should generally be examined within the next few days to two weeks, depending on severity.

Bring:

• Medication list

• Water-intake record

• Urination history

• Photographs

• Insulin and glucose records for a diabetic pet

• Details of previous endocrine tests

8. Handle cats with fragile skin carefully

If feline Cushing’s syndrome is possible:

• Do not lift the cat by loose skin

• Avoid tight restraint

• Use padded bedding

• Keep claws trimmed safely

• Avoid rough grooming

• Tell every clinic team member that the skin may tear

• Avoid tight harnesses or adhesive dressings unless professionally applied

Common Mistakes Owners Make

Assuming the signs are normal ageing

Older animals may slow down, but marked thirst, constant hunger, persistent panting and progressive muscle loss are not changes that should simply be accepted.

Testing because alkaline phosphatase is high

An elevated canine alkaline phosphatase is supportive but not diagnostic. Many medications and diseases increase it.

Endocrine testing is most useful when compatible clinical signs are present.

Restricting water

Water restriction can worsen dehydration and does not correct the cause of excessive urination.

Forgetting ear, eye and skin steroids

Topical glucocorticoids still count. Always tell the veterinarian about every steroid-containing product.

Stopping long-term steroids suddenly

Abrupt withdrawal can cause dangerous adrenal insufficiency. A veterinary taper is required.

Assuming every poorly controlled diabetic cat has Cushing’s syndrome

Feline Cushing’s is rare. More common causes of insulin resistance should be investigated first.

Assuming vomiting and diarrhoea are routine canine Cushing’s symptoms

They are not. These signs suggest another disease, a complication or excessive cortisol suppression during treatment.

Treating the laboratory result instead of the patient

Cushing’s syndrome is a clinical syndrome. A borderline test result without compatible signs does not automatically justify lifelong treatment.

Can Cushing’s Syndrome Be Prevented?

Naturally occurring pituitary and adrenal tumours cannot usually be prevented.

Risk from medication can be reduced by:

• Using glucocorticoids only under veterinary direction

• Using the lowest effective dose

• Avoiding unnecessary repeated long-acting injections

• Reviewing ongoing steroid requirements regularly

• Monitoring dogs receiving chronic steroid treatment

• Reporting increased thirst, appetite or panting

• Never combining steroid products without veterinary advice

• Tapering medication appropriately

No diet, supplement, herbal product or exercise programme has been proven to prevent naturally occurring Cushing’s syndrome.

Routine veterinary examinations and senior-pet screening can help detect the clinical pattern earlier.

What Happens After Diagnosis?

Treatment depends on the cause.

Dogs

Options may include:

• Trilostane to control cortisol production

• Adrenalectomy for suitable adrenal tumours

• Pituitary surgery at specialist centres

• Radiation therapy for selected pituitary tumours

• Management of diabetes, hypertension, infection or gallbladder disease

• Adjustment and gradual withdrawal of causative steroid medication

Trilostane is commonly used for both pituitary-dependent and adrenal-dependent disease. Clinical signs and safety testing must be monitored regularly, especially during the first month and after dose changes.

Cats

Treatment may include:

• Trilostane

• Adrenalectomy for a suitable adrenal tumour

• Transsphenoidal pituitary surgery at specialist centres

• Radiation therapy in selected cases

• Intensive diabetic management

• Treatment of infection and skin wounds

Feline treatment can be challenging, but clinical improvement is possible. Trilostane is currently the principal medical treatment, while adrenalectomy or hypophysectomy may be potentially curative in selected cats.

Will Your Dog or Cat Be Okay?

Many dogs with Cushing’s syndrome can maintain a good quality of life when the disease and its complications are properly controlled.

With successful treatment, owners may notice improvement in:

• Thirst

• Urination

• Appetite

• Panting

• Energy

• Muscle function

These changes may improve over weeks. Coat and skin recovery generally takes longer and may require several months. Most treated dogs do well when medication is adjusted according to both clinical response and appropriate monitoring.

The outlook for cats is more guarded because the disease is often diagnosed after severe diabetes, muscle loss or skin fragility has developed. Nevertheless, successful medical or surgical treatment can improve cortisol-related signs and may make diabetes easier to manage in some cats.

The prognosis depends on:

• Pituitary versus adrenal disease

• Tumour size and behaviour

• Presence of diabetes

• Kidney and liver health

• Blood pressure

• Blood-clot risk

• Skin damage

• Concurrent infection

• Response to treatment

• Ability to monitor safely

The goal is not simply to produce a particular cortisol number. It is to reduce thirst, hunger, panting, weakness, infection and other complications while avoiding cortisol deficiency.

Frequently Asked Questions

Is Cushing’s syndrome painful?

The hormonal disorder itself is not usually directly painful. Complications such as calcinosis cutis, skin infection, gallbladder disease, blood clots, fragile-skin wounds and diabetic neuropathy can be painful.

Can Cushing’s syndrome cause vomiting or diarrhoea?

Uncomplicated canine Cushing’s syndrome does not usually cause vomiting, diarrhoea or reduced appetite. These signs suggest another illness, a complication or excessive suppression from treatment. Gastrointestinal signs can occur in cats, but they are considered uncommon.

Can a pet have Cushing’s syndrome without a pot belly?

Yes. Not every affected animal develops every classic sign. Earlier cases may show only increased thirst, urination, appetite, panting or subtle skin changes.

Can cats really develop Cushing’s syndrome?

Yes, but it is rare. Most affected cats are middle-aged or older and many have concurrent diabetes mellitus. Fragile skin, abdominal enlargement, muscle wasting and poor hair regrowth are particularly important clues.

Does one positive Cushing’s test confirm the diagnosis?

Not necessarily. Every available test has limitations, and stress or other illness may produce misleading results. The result must be interpreted alongside clinical signs, routine laboratory findings, medication history and imaging.

Final Thoughts

Cushing’s syndrome rarely announces itself with one dramatic symptom.

In dogs, the pattern is usually gradual: more drinking, more urination, more hunger, more panting, less muscle and a slowly changing body shape or coat.

In cats, the pattern is different. Difficult diabetic control, progressive muscle wasting, abdominal enlargement and skin that becomes thin enough to tear are the strongest warning signs.

What matters most is the combination and direction of change. A slightly rounded abdomen means little on its own. A rounded abdomen combined with excessive thirst, ravenous appetite, muscle loss and poor hair regrowth deserves investigation.

Do not test solely because one liver enzyme is high. Do not assume every ageing change is harmless. Do not stop steroid medication abruptly. Most importantly, do not ignore acute illness because your pet already has, or may have, Cushing’s syndrome.

Breathing difficulty, collapse, seizures, sudden blindness, vomiting, diarrhoea, refusal to eat or profound weakness changes the situation from a chronic endocrine investigation to an urgent medical problem.

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If you are unsure whether your dog or cat’s thirst, body changes, skin problems or diabetic control could indicate Cushing’s syndrome, ASK A VET™ can help you organise the signs and prepare the right questions for your veterinary team.