Shaking and vomiting in an old dog are symptoms that can be frightening to see, especially when they appear suddenly or worsen quickly.
Senior dogs are more vulnerable to many conditions that can cause nausea, trembling, or full-body weakness, so understanding the possible causes is essential for getting help early.
We outline the common causes of shaking and vomiting in old dogs, what you can do at home, and when to seek veterinary help.
Old Dog Shaking and Vomiting: Why It Happens
An old dog shaking and vomiting is typically experiencing discomfort, nausea, pain, or a more serious underlying medical condition that affects digestion, internal organs, or the nervous system. As dogs age, their bodies become less efficient at managing stress, fighting infections, and processing food or toxins.
Issues such as gastrointestinal inflammation, pancreatitis, kidney disease, toxin exposure, or severe dehydration can trigger both trembling and vomiting at the same time.
Many of these conditions cause nausea, electrolyte imbalances, or abdominal pain, which explains why the shaking and vomiting appear together in senior dogs.
Old Dog Shaking and Vomiting: Common Causes
Gastroenteritis
Gastroenteritis is one of the most common causes of vomiting in old dogs and happens when the stomach and intestines become inflamed.
For senior dogs, even a mild upset can escalate into more severe symptoms like shaking because their bodies have a harder time balancing fluids and electrolytes.
When the digestive tract becomes irritated, vomiting starts as the body attempts to expel whatever is causing the problem.
This sudden loss of fluids can make an old dog weak or trembly. Some dogs shake from discomfort, while others shake because the inflammation affects their temperature regulation.
Loss of appetite, burping, drooling, and fatigue often appear alongside vomiting. While younger dogs may bounce back quickly, senior dogs can decline rapidly, making gastroenteritis more serious in old age.
Related: Old dog constant diarrhea (Why it happens)
Pancreatitis
Pancreatitis is a major cause of vomiting and shaking in older dogs. The pancreas becomes inflamed, leading to severe abdominal pain, nausea, and digestive upset. Because the pancreas plays a central role in digestion, inflammation causes vomiting to start suddenly and persistently.
Shaking is common because pancreatitis is painful. The tremors can worsen when the dog tries to move or lie down.
Senior dogs often avoid eating because food worsens the discomfort, and abdominal tenderness makes them restless or shaky.
Pancreatitis can be triggered by fatty foods, endocrine disorders, or no clear cause at all, especially in older dogs.
It is a condition that needs prompt treatment because repeated vomiting can lead to dehydration, electrolyte imbalances, and system-wide complications.
Kidney Disease
Kidney disease is extremely common in old dogs and often causes gradual symptoms that worsen over time. When the kidneys begin to fail, toxins build up in the bloodstream, leading to nausea and vomiting.
Shaking occurs when toxins affect the dog’s nervous system, when electrolyte levels drop, or when the dog becomes dehydrated.
Old dogs with kidney issues may also seem lethargic, stumble, develop bad breath, or drink and urinate more frequently.
Vomiting caused by kidney disease is often persistent and may be accompanied by weight loss or decreased appetite.
Because the kidneys cannot remove waste efficiently, the body becomes overwhelmed, and shaking becomes a sign that the dog is struggling internally.
Toxin Exposure
Even in old age, dogs may ingest something harmful—such as spoiled food, medications, plants, or household chemicals. Senior dogs can be less resilient to toxins because their organs process substances more slowly.
Vomiting shows up quickly as the body tries to remove the toxin. Shaking may appear alongside vomiting because toxins can affect the nervous system, cause muscle weakness, or trigger severe nausea.
Some toxins, such as xylitol, rat poison, or antifreeze, can cause rapid organ failure in old dogs. Even common household items like chocolate or grapes are far more dangerous to senior dogs than to young, healthy dogs.
If vomiting and shaking come on suddenly and severely, toxin exposure must be considered.
Severe Dehydration
Old dogs dehydrate faster than younger dogs, especially when vomiting is involved. When fluid levels drop, the dog may tremble, appear weak, or struggle to stand.
Dehydration also interferes with circulation and the body’s ability to regulate temperature, which is why shaking becomes more noticeable.
As dehydration worsens, vomiting may continue because the stomach becomes irritated and the body cannot maintain proper balance.
Dry gums, sunken eyes, and lethargy often accompany these symptoms. Severe dehydration is dangerous in senior dogs and can lead to organ failure if not treated quickly.
Pain
Many elderly dogs experience pain from arthritis, back issues, or abdominal inflammation. Pain itself can cause shaking, and the discomfort may lead to nausea or vomiting.
Internal inflammation, such as from liver disease or gallbladder problems, often causes repeated vomiting. Trembling may signal that the old dog is struggling with discomfort or cannot get comfortable.
Senior dogs hide pain more often than younger dogs, so shaking combined with vomiting may be one of the first noticeable signs of a deeper issue.
Related: Dog shaking and not eating (Causes explained)
What to Do If Your Old Dog Is Shaking and Vomiting
When an old dog is shaking and vomiting, the first priority is to keep them comfortable and monitor their symptoms. Allow your dog to rest in a calm, warm environment, as shaking can worsen when they are stressed or cold.
Avoid offering food until vomiting has paused for a couple of hours, but you may provide small sips of water or an electrolyte solution if they can keep it down.
Because senior dogs are more vulnerable, even a few episodes of vomiting can lead to dehydration.
Check their hydration by lifting the skin at the back of the neck—if it returns slowly, they may already be dehydrated. If your dog continues shaking, seems weak, or refuses water, veterinary attention is important.
Do not give over-the-counter medications meant for humans, as they can be dangerous for dogs, especially older ones. If you suspect they may have eaten something toxic, gather any packaging or information that could help the veterinarian identify the substance.
Keep your old dog warm with a soft blanket and minimize their movement if shaking appears to be related to pain or weakness.
Sometimes the trembling improves once the dog is resting in a comfortable position, but if it continues, it may indicate a deeper issue such as pancreatitis or kidney disease.
Watch for any additional signs such as diarrhea, collapse, pale gums, or abdominal swelling, as these require urgent care.
When to Call or Visit Your Vet
Seek veterinary care immediately if the vomiting is continuous, if your old dog cannot keep even small amounts of water down, or if the shaking becomes more intense. Old dogs can become dehydrated or unstable quickly, and early treatment makes a major difference.
Contact your vet right away if your dog shows signs of pain, such as whining, a hunched posture, or reluctance to move.
Vomiting with blood, dark tar-like stools, or projectile vomiting are also urgent warning signs.
If your old dog has a known chronic condition—such as kidney disease, diabetes, or heart disease—and begins shaking and vomiting, do not wait to see if symptoms improve. These dogs are more fragile and may decline rapidly.
Difficulty standing, collapsing, or shaking that does not stop even after vomiting ends should be considered an emergency. These symptoms can point to shock, severe dehydration, toxin exposure, pancreatitis, or organ failure.
Read more: Dog Shaking and Vomiting (Here’s why)
Key Takeaway
Shaking and vomiting in an old dog are symptoms that should always be taken seriously. Senior dogs are more vulnerable to conditions like pancreatitis, kidney disease, dehydration, and gastrointestinal inflammation—all of which can escalate quickly without treatment.
While mild stomach upset can occasionally resolve with rest, the combination of shaking and vomiting suggests a deeper issue that deserves prompt attention.
Supporting your old dog at home and seeking veterinary care early provides the best chance for recovery.
Trust your instincts—if your senior dog seems weak, distressed, or unable to keep fluids down, getting help right away is the safest choice.