When your dog is shaking and not eating and lethargic, it’s a sign that something isn’t right.
These symptoms may point to anything from temporary discomfort to a serious health condition that needs urgent attention.
We outline the most common causes of a dog shaking and not eating and lethargic behavior, explain how these signs are linked, and guide you on what to do and when to seek veterinary help.
Dog shaking and not eating and lethargic: Why It Happens
The combination of shaking, not eating and lethargy symptoms usually signals that your dog is unwell or in distress. A dog shaking and not eating and lethargic may be reacting to pain, infection, poisoning, stress, or an underlying medical condition such as gastrointestinal upset, kidney disease, or low blood sugar.
These signs often occur together because illness or discomfort can suppress appetite and energy levels, while shaking may reflect internal pain, fever, or neurological issues.
It’s a clear sign that something is wrong and often requires prompt veterinary attention.
Common Causes of Dog Shaking and Not Eating and Lethargic Behavior
1. Pain or injury
Pain is one of the most common reasons why a dog may be shaking and not eating and lethargic.
Dogs may shake due to internal or external injuries, joint pain, muscle strain, or trauma.
Even if no wound is visible, internal injuries or conditions like arthritis, pancreatitis, or intervertebral disc disease can cause enough pain to trigger tremors and make your dog withdraw from food and activity.
A dog in pain may also show other signs such as whining, limping, or hiding.
If you notice these alongside shaking and lethargy, consult your vet promptly.
Related: Dog diarrhea and not eating (Explained)
2. Infections
Bacterial or viral infections such as parvovirus, distemper, or leptospirosis can make your dog feel sick and weak.
These infections commonly present with symptoms like vomiting, fever, trembling, diarrhea, not eating, and extreme fatigue.
In some cases, they can be life-threatening if not treated in time.
Puppies and unvaccinated dogs are at a particularly high risk.
If your dog suddenly stops eating, appears tired, and is shaking, especially with vomiting or diarrhea, don’t delay seeking medical help.
3. Toxin ingestion or poisoning
If your dog is shaking and not eating and lethargic, poisoning must be considered.
Dogs can be exposed to toxins through food (like chocolate, grapes, or xylitol), chemicals (like antifreeze or pesticides), or even certain plants.
Shaking can be a neurological response to the toxin, while lethargy and appetite loss are systemic reactions.
Some toxins can also cause seizures, vomiting, or collapse.
Always monitor your dog’s environment and contact your vet immediately if you suspect poisoning.
4. Gastrointestinal problems
Conditions such as pancreatitis, gastritis, or a gastrointestinal blockage can cause abdominal pain, nausea, and inflammation—leading your dog to become lethargic, refuse food, and shake.
Dogs experiencing GI discomfort might also display symptoms such as vomiting, bloating, or restlessness.
A vet will need to perform a physical exam and possibly imaging tests to determine the cause and appropriate treatment.
5. Stress and anxiety
Stress can manifest physically in dogs. Emotional triggers like loud noises (thunderstorms, fireworks), separation anxiety, or sudden changes in their environment can cause a dog to tremble.
In stressed dogs, the shaking may be accompanied by lethargy or reluctance to eat.
While temporary anxiety may resolve on its own, prolonged anxiety can lead to health issues, such as gastrointestinal upset or chronic fatigue, making your dog feel increasingly unwell.
Related: Dog is Vomiting, Has Diarrhea, and Not Eating (Causes and What to do)
6. Neurological issues
Neurological conditions, such as seizures or vestibular disease, can cause shaking, poor coordination, and confusion.
Dogs with such disorders may seem disoriented, not want to eat, and sleep excessively.
Neurological causes can be harder to detect without imaging or diagnostic tests, but if your dog shows uncoordinated movement along with shaking and not eating and lethargic behavior, a neurological evaluation is needed.
7. Low blood sugar (hypoglycemia)
Hypoglycemia is a common issue in puppies, small breeds, and diabetic dogs.
When blood sugar drops too low, it can cause shaking, weakness, lack of energy, and refusal to eat.
In severe cases, it can lead to seizures or collapse.
If your dog hasn’t eaten in a while and suddenly becomes shaky and lethargic, low blood sugar could be the cause.
Offering a small amount of sugar water can help in emergencies—but always follow up with your vet.
8. Fever or overheating
A dog with a high fever or heat exhaustion may show signs of shivering, poor appetite, and lethargy.
Fever can be triggered by infections, inflammation, or immune responses.
Heatstroke, particularly in hot climates or after vigorous activity, can cause panting, drooling, shaking, and collapse.
Always ensure your dog is well hydrated and never overexerted during hot weather.
9. Kidney or liver disease
Dogs suffering from chronic illnesses such as kidney disease or liver failure often display vague symptoms in the early stages—such as shaking, not eating, and low energy levels.
As toxins build up in the bloodstream, it affects appetite, energy levels, and can cause nausea and tremors.
Blood tests are essential to diagnose these conditions, and early treatment can help manage or slow disease progression.
What to do if your dog is shaking and not eating and lethargic
If your dog is shaking and not eating and lethargic, here’s what you should do:
1. Check for other symptoms
Take note of any accompanying signs—vomiting, diarrhea, limping, fever, gum color, breathing changes, or signs of pain.
These help your vet identify the potential cause.
2. Keep your dog calm and comfortable
Minimize stimulation by keeping your dog in a quiet, dimly lit area.
Offer water and soft food, but do not force-feed. Monitor breathing, body temperature, and responsiveness.
3. Do not give human medication
Avoid giving your dog over-the-counter or human medications like ibuprofen or acetaminophen.
Many human drugs are toxic to dogs and can worsen the condition.
4. Contact your veterinarian promptly
If symptoms persist for more than a few hours, or if your dog worsens, get in touch with a veterinarian immediately.
Timely diagnosis and treatment can make a significant difference in outcomes.
Seek emergency help immediately if your dog:
Is unresponsive or very weak
Has a seizure
Is vomiting blood or has bloody diarrhea
Is a puppy, senior, or chronically ill
Has signs of poisoning
Has rapid breathing or extreme panting
Key takeaway
A dog shaking and not eating and lethargic is not just a random occurrence—it’s often a red flag for a deeper issue.
Whether it’s an infection, poisoning, internal pain, or a chronic condition, early detection is critical.
Keep a close eye on your pet’s behavior, hydration, and appetite, and never hesitate to consult a vet when your dog displays multiple troubling symptoms.
By acting promptly and getting veterinary support when needed, you can give your dog the best chance for a full recovery and continued health.