When your puppy is shaking and not eating, it can be deeply concerning. Puppies are typically full of energy and eager to eat. When you notice your puppy shaking and not eating, it could signal a serious underlying problem or a temporary issue that needs monitoring.
We outline the common reasons your puppy may be shaking and not eating, the symptoms to watch for, and when to seek veterinary care.
Puppy Shaking and Not Eating: Why It Happens
Puppy shaking and not eating can happen due to several underlying causes that affect their physical or emotional well-being.
Common reasons include low blood sugar (hypoglycemia), cold temperatures, stress or anxiety, gastrointestinal issues, parvovirus or other infections, pain or injury, poisoning or toxin exposure, fever or inflammation, and side effects from vaccinations.
These issues may interfere with a puppy’s normal appetite and cause trembling due to discomfort, illness, or metabolic imbalance.
Common Causes of Puppy Shaking and Not Eating
Low blood sugar (hypoglycemia)
One of the most common reasons for a puppy shaking and not eating is low blood sugar.
This is especially true in toy and small breeds, which are more susceptible due to their tiny energy reserves.
When a puppy skips a meal or plays too hard without eating, their glucose levels can drop quickly, leading to weakness, trembling, and disinterest in food.
Hypoglycemia in puppies can become life-threatening if not treated quickly.
You may also notice signs such as staggering, disorientation, or collapse.
Related: Dog shaking and not eating (Causes and what to do)
Cold temperatures
Young puppies have a harder time regulating their body temperature.
If your puppy is shaking and not eating and is also cold to the touch, hypothermia could be the cause.
Being exposed to a chilly room, a cold floor, or drafty areas for too long can trigger this.
A cold puppy may try to conserve energy, which can result in a loss of appetite along with trembling.
Stress or anxiety
Stress is another major reason for puppy shaking and not eating.
Puppies are highly impressionable and sensitive to their environment.
Situations like traveling, loud noises, changes in routine, new surroundings, or being separated from their litter can trigger anxiety.
A stressed puppy may refuse food, shake, hide, or whimper.
These stress responses often subside as the puppy becomes more familiar and comfortable with their surroundings.
Gastrointestinal issues
Digestive upset can also explain why your puppy is shaking and not eating.
Puppies often eat things they shouldn’t — including spoiled food, plants, and household objects.
This can lead to vomiting, diarrhea, bloating, or constipation, which can be painful and reduce appetite.
In severe cases, a gastrointestinal obstruction (blockage) could be the culprit. Obstructions are dangerous and may require emergency surgery.
Trembling, belly pain, vomiting, and complete loss of appetite are classic signs.
Parvovirus or other infections
Puppies that haven’t completed their vaccinations are vulnerable to dangerous infections such as parvovirus.
A puppy shaking and not eating can be an early warning sign, especially if it’s followed by vomiting, diarrhea (often bloody), or extreme lethargy.
Other possible infections include distemper, leptospirosis, or kennel cough.
These illnesses can cause systemic symptoms such as tremors, fever, coughing, nasal discharge, and lack of appetite.
Early veterinary treatment is crucial to give your puppy the best chance of recovery from infectious diseases.
Pain or injury
A puppy shaking and not eating might be in pain from an injury or an internal issue.
Dogs often hide signs of pain, but trembling, restlessness, and not wanting food are common giveaways.
This pain might come from teething, abdominal discomfort, trauma, or an undetected injury from playing or falling.
In some cases, shaking is localized — such as a leg tremor — while in others, the entire body is affected.
Poisoning or toxin exposure
Puppies are curious and prone to licking, chewing, and swallowing unfamiliar substances.
Toxic substances like chocolate, xylitol (a sugar substitute found in gum), cleaning agents, and certain plants can all trigger symptoms.
A puppy that is shaking and not eating may have ingested a toxin.
This can be life-threatening and often comes with other symptoms such as vomiting, diarrhea, drooling, weakness, and seizures.
Fever or inflammation
Fever in puppies can make them feel cold internally, leading to shivering and shaking.
A puppy may also lose its appetite when running a fever, regardless of the cause — whether it’s an infection or inflammatory illness.
Checking your puppy’s body temperature can help determine if a fever is present.
Normal rectal temperature in puppies ranges from 101°F to 102.5°F (38.3°C to 39.2°C).
Vaccination side effects
Sometimes, a puppy shaking and not eating can be a response to a recent vaccination.
Vaccines can occasionally cause mild side effects such as fever, soreness, lethargy, and reduced appetite.
These reactions are generally short-lived and resolve within 24–48 hours. However, if your puppy’s symptoms persist or worsen, contact your vet.
What to do if your puppy is shaking and not eating
If you notice your puppy shaking and not eating, here’s how you can help and when to take action:
1. Monitor other symptoms:
Check for additional signs such as vomiting, diarrhea, lethargy, limping, pain, or unusual behavior.
These will help determine how serious the issue might be.
2. Warm them up:
If your puppy feels cold, gently warm them with a soft blanket or heating pad (on a low setting).
Make sure they aren’t too hot — overheating can also be harmful.
3. Offer food or a glucose solution:
Try offering your puppy a small amount of their favorite food or a teaspoon of honey or Karo syrup on their gums (especially if you suspect low blood sugar).
If they still refuse to eat, don’t force them — this could cause more stress.
4. Provide a calm environment:
Reduce noise and activity to lower their stress.
Speak softly and stay nearby to reassure your puppy.
5. Check for toxins:
Look around for any potential poisons or items your puppy may have ingested.
This includes houseplants, cleaning products, human food, or medications.
6. Do not delay veterinary care:
If your puppy continues to shake and not eat for more than a few hours, or if other symptoms like vomiting, diarrhea, or lethargy appear, consult your vet right away.
Puppies can deteriorate quickly, and early treatment is critical.
When to seek emergency care
You should contact a veterinarian immediately if:
Your puppy is shaking uncontrollably
There is vomiting or diarrhea (especially with blood)
Your puppy becomes lethargic or unresponsive
Signs of poisoning are present
Your puppy has a fever or seems in pain
Your puppy is younger than 8 weeks and hasn’t eaten for several hours
Puppies are fragile and don’t have strong immune systems yet, so timely intervention can be life-saving.
Key Takeaway
A puppy shaking and not eating can be caused by a variety of issues ranging from mild to serious.
While stress, cold, or minor digestive issues may resolve on their own, more severe conditions like infections, poisoning, or hypoglycemia require prompt medical care.
Always pay attention to your puppy’s behavior and trust your instincts.
If something feels wrong, it’s better to err on the side of caution and consult your vet.
Acting quickly can protect your puppy’s health and ensure a long, happy life ahead.