If you’ve been managing your dog’s Cushing’s disease and suddenly notice they’ve stopped eating, it’s understandable to feel anxious. Cushing’s disease can be complex and unpredictable, and a loss of appetite may be your dog’s way of signaling that something isn’t quite right—whether related to the condition itself or a complication of treatment.
In this blog, we’ll cover why your dog may stop eating with Cushing’s, what you can do at home, and when it’s time to reach out to your vet.
My Dog Has Cushing’s and Is Not Eating — Why It Happens
When a dog has Cushing’s and is not eating, it may be due to medication side effects (especially from Vetoryl or Lysodren), gastrointestinal upset, secondary infections, adrenal crises, elevated cortisol levels, or disease progression. Appetite changes often signal an imbalance in treatment, additional illness, or discomfort that needs veterinary attention.
Dog Has Cushing’s Disease and Not Eating: Common Causes
1. Medication Side Effects (Vetoryl or Lysodren)
The most common treatment for Cushing’s disease is Vetoryl (trilostane) or Lysodren (mitotane), both of which aim to regulate the overproduction of cortisol. However, if the dosage is too high or not well-tolerated, it can suppress the adrenal glands too much, leading to lethargy, nausea, vomiting, and appetite loss.
Watch for:
Sudden decrease in energy
Vomiting or diarrhea
Shaking or collapse
Refusal to eat even favorite treats
If your dog started a new medication or recently had a dose adjustment, contact your vet right away. Blood testing may be needed to reassess hormone levels.
2. Adrenal Crisis or Addisonian Reaction
In rare cases, overmedication for Cushing’s can lead to a condition called iatrogenic Addison’s disease, where cortisol levels drop dangerously low. This is considered an emergency and can cause:
Sudden inappetence
Severe vomiting or diarrhea
Weakness or collapse
Dehydration and shock-like symptoms
This reaction requires immediate veterinary intervention, often with IV fluids, electrolyte support, and steroids.
Related: Dog vomiting and not eating (Causes and when to worry)
3. Gastrointestinal Upset
Dogs with Cushing’s are more prone to gastrointestinal problems, either due to elevated cortisol levels or long-term use of steroids. Conditions like ulcers, gastritis, or pancreatitis can lead to nausea and food refusal.
Look for:
Lip licking or swallowing
Vomiting or retching
Lying in a hunched position
Disinterest in water or food
A bland diet and temporary GI-supportive medications may help, but persistent symptoms warrant vet evaluation.
4. Progression of the Disease
In advanced cases of Cushing’s, the body becomes more susceptible to muscle wasting, fatigue, liver enlargement, and immune suppression. These effects can contribute to general discomfort and loss of appetite over time.
Symptoms may include:
Weakness in the limbs
Belly distension
Lethargy and reduced interaction
Sleeping more and eating less
It’s important to track your dog’s appetite, weight, and energy levels closely as part of their ongoing care plan.
5. Infections or Concurrent Illnesses
Dogs with Cushing’s have weakened immune systems, making them more vulnerable to infections—especially of the urinary tract, skin, or respiratory system. A developing infection may cause your dog to feel unwell and stop eating.
Signs of possible infection:
Fever
Foul-smelling urine or frequent accidents
Coughing or sneezing
Skin sores or abscesses
A vet visit, urinalysis, or blood test may be required to diagnose and treat underlying infections promptly.
6. Stress or Changes in Routine
Dogs with Cushing’s may become more sensitive to environmental changes. A recent move, new pet, house guests, or even loud construction nearby could cause your dog to become anxious and skip meals.
Behavioral signs include:
Pacing or panting
Hiding or avoiding contact
Sudden disinterest in food or water
Creating a calm, consistent routine and offering meals in a quiet area can help ease their stress.
What to Do If Your Dog Has Cushing’s and Stops Eating
If your dog is stable and alert, try these steps at home:
Offer bland, soft meals such as boiled chicken, turkey, or rice
Warm food slightly to enhance smell and stimulate interest
Feed smaller meals more frequently if large meals seem overwhelming
Limit treats and rich food that may upset the stomach
Keep a symptom log including appetite, water intake, and behavior
Make sure your dog is drinking water. Dehydration can quickly worsen symptoms, especially in dogs on diuretics or steroids.
When to Call or Visit Your Vet
Reach out to your vet promptly if:
Your dog hasn’t eaten for more than 24 hours
Vomiting, diarrhea, or tremors are present
There’s sudden lethargy, shaking, or collapse
They’ve recently had a medication adjustment
You suspect an infection or adrenal crisis
Your vet may run an ACTH stimulation test, electrolyte panel, or imaging to evaluate cortisol levels and rule out secondary problems.
Related Blogs
Read more: [Dog Vomiting and Not Eating But Drinking Water]
Related: [Dog Lethargic Not Eating and Vomiting]
Read more: [Dog Tired and Not Eating]
Related: [Dog Always Sleeping and Not Eating]
Read more: [Dog Dehydrated and Not Eating]
These articles cover similar symptoms that commonly overlap with complications from Cushing’s disease.
Final Thoughts
If your dog has Cushing’s and is not eating, don’t ignore it. Appetite loss in these dogs can point to serious underlying issues, especially related to medication dosage, gastrointestinal distress, or secondary illness. With careful observation, open communication with your vet, and supportive care, most cases can be managed before complications worsen.
Trust your instincts and act early—your attentiveness plays a key role in keeping your dog healthy and comfortable during their journey with Cushing’s.
✅ Up next: Dog Choking and Not Eating — just say “Continu