Trembling or shaking can be a telltale sign your dog is feeling particularly cold or fearful, but it can also be an indicator that they are sick or in pain. Understanding some of the common behavioral, medical, and genetic reasons for shaking in dogs can help you better evaluate if there is a cause for concern and whether an emergency trip to the vet or a behavior consult is required.
Here are some of the possible reasons why dogs shake.
Puppies, elderly, small, sick or underweight dogs, and those bred to live in hot regions are more sensitive to cold weather. So, a spitz-type breed, like a Siberian Husky, with its thick double coat, is much less likely to shiver when the temperatures drop when compared to a svelte, single-coated Greyhound.
You aren’t pandering to your pup if you invest in a practical coat, an extra blanket or two, and a cozier, draft-free spot in your home. Prolonged exposure to cold temperatures can lead to hypothermia in dogs. If you have to do shorter walks to limit their exposure, you can keep them mentally and physically stimulated with some puzzle games and other in-house enrichment.
Fear or anxiety
Shaking can be a physiological response to fear, stress, or anxiety. Some dogs are naturally more fearful than others, or particular stimuli can trigger an individual’s anxieties. Typically, other indicators that your dog is not feeling relaxed accompany the shivering, like excessive panting, pacing, whining, cowering, or drooling.
Some dogs will try to hide, and others may display signs of aggression or destructive behavior. Observe your dog’s body language and consider any changes in the environment or their routine. Common triggers include moving home, separation anxiety, thunderstorms, fireworks, or vet visits.
Implementing a desensitization and counterconditioning behavior modification program can help alleviate your dog’s anxiety around the trigger and elicit a more positive association. Consultation with a qualified veterinary behaviorist could be necessary in severe cases, and complementary drug therapies can also be prescribed.
You don’t always have to worry if your dog is shaking. Sometimes it can result from being happy and excited. They might see you returning home after a day of work and start trembling in anticipation of greeting you.
This excited shaking can become problematic, however, if your dog is frequently in an over-aroused state. It can create impulse control issues, stress, and hypervigilance. You may need to work on lowering their levels of excitement around triggers or give them appropriate alternative mental enrichment and training exercises.
If your dog is clever enough, perhaps they noticed that they got attention from you when they were shaking from the cold. They could learn to simulate shaking as attention-seeking behavior, which you unintentionally reinforce when you give them what they want. If you are sure this is a learned behavior, waiting until the shaking has ceased before you offer any attention will usually resolve this issue.
Pain relating to an injury or illness can cause a stress reaction in a dog’s body, resulting in violent trembling. Nausea, medication side effects, and various diseases can also induce full-body shaking, while some conditions produce tremors isolated to certain parts of the body. The medical conditions below can all cause full-body shaking in dogs.
1. Toxin exposure
If your dog has ingested a poisonous substance, this can impact the nervous system and cause them to tremble. Some toxins can also cause acute pain, and this in itself can induce shaking. The toxicity symptoms and severity will depend on what your dog ingested, in what quantity, and when. Symptoms could include gastrointestinal problems, lethargy, hyperactivity, confusion, or seizures.
The ASPCA Animal Poison Control Center reported that the top pet toxins of 2020 included human medications, cleaning products, chocolate, rodenticides, and certain plants. If you suspect your dog has ingested a poisonous substance, don’t delay in seeking veterinarian support. The 24-hour Pet Poison Helpline can also provide round-the-clock advice.
2. Muscle weakness or fatigue
Senior dogs often experience muscle atrophy, particularly in their hind quarters. Consequently, their legs become more easily fatigued, and you might spot trembling until they rest. Appropriate diet and exercise can help to support your dog’s muscle condition into their later years. Dogs involved in high impact sports or strenuous activity can also experience shaking as a result of overexertion.
Hypocalcemia is a calcium deficiency in the blood. Various conditions can trigger this issue, including kidney problems, pancreatitis, rickets in young puppies, and hypoparathyroidism. Alongside shivering and muscle twitching, other symptoms include vomiting, lethargy, uncoordinated gait, inappetence, fever, and panting.
Low blood sugar levels can also induce shaking in dogs. Hypoglycemia is commonly associated with diabetes and an overdose of insulin, but other conditions—such as Addison’s disease, certain drugs, and toxins—can also be triggers. It is a serious condition that requires prompt treatment. Other symptoms include blurred vision, confusion, changes in appetite, increased thirst, and lethargy.
5. Seizure disorders
Of all the neurological conditions that dogs can suffer from, seizures are one of the most widely reported. The severity of these involuntary brain disturbances can vary greatly, and the uncontrollable muscle activity can range from light trembling or tremors to full-body convulsions. During a seizure, your dog will typically be unconscious. Even if you haven’t witnessed the actual episode, afterwards your dog may still tremble and seem confused and disorientated.
Epilepsy is the term used when a dog suffers from repeated seizures. Idiopathic epilepsy is an inherited disorder with an unknown cause, but seizures can also be associated with things like head trauma, brain cancer, ingestion of toxins, kidney or liver disease, and strokes.
If you witness your dog having a suspected seizure, veterinary support is important. Severe, prolonged, and cluster seizures can lead to brain damage and will require investigation to understand if there is any underlying cause. For idiopathic epilepsy, medication is often required to keep the seizures under control.
Shaking is more common in small dog breeds
Non-medical related shaking is more common in smaller dogs. Chihuahuas, for example, are known for their tendency to tremble. The exact reasons for this aren’t known, but their size and fast metabolism makes them more susceptible to the cold, and excited and fear-based shaking are not uncommon.
Generalized Tremor Syndrome (GTS)
Small breeds, particularly white-coated ones like Maltese and West Highland Terriers, are also susceptible to GTS (also known as Shaker Syndrome). This idiopathic condition typically manifests in young dogs around one to two years old. It results in all over body shaking or, less commonly, involuntary muscle contractions isolated to a particular area. Owners often initially mistake the symptoms as being associated with the cold or anxiety.
The intensity of the tremors can increase during periods of exercise, stress, or excitement and typically lessen when resting. Fortunately, this syndrome usually responds well to steroids, which is why it is also known as Steroid Responsive Tremors.
The difference between tremors and shaking in dogs
It is worth noting that tremors are often described as the same as all-over body trembling by concerned pet parents when visiting the vets, but they are distinctly different things.
Tremors are involuntary and rhythmic contractions of the muscles. Unlike general all-over body trembling, they are often isolated to one or a couple of body parts and usually only happen when the dog is awake. Tremors are intermittent or constant and can become more pronounced over time. Videoing the tremors your dog is experiencing can be a useful illustrative tool should you need to consult with a vet.
Some other conditions which are more likely to cause tremors or twitching rather than, or as well as, general shaking include muscle diseases (like Tetanus), acquired diseases (like Cushing’s), and conditions affecting the nervous system (commonly in the cerebellum of the brain or viruses like Distemper). Some of the toxins that can cause tremors include certain rodenticides/insecticides, mycotoxins (sometimes in moldy trash or compost), theobromine and caffeine (the toxic components of chocolate) and amphetamines.
When to see a veterinarian
If you’ve ruled out behavioral causes for trembling, it’s always a good idea to consult with a vet, especially if other symptoms accompany the shaking or it has continued for more than a couple of hours.
If there aren’t any other obvious symptoms like vomiting or diarrhea, look out for more subtle changes in your dog’s behavior that would indicate they are in pain. Perhaps they are more clingy or, conversely, unusually withdrawn and shying away from your touch. Maybe they are panting excessively, looking tense or stiff, or lethargic. They might have gone off their food or not be able to settle. The more information you can give your vet about any additional symptoms, not just the shaking, the easier it will be for them to get to the root of the problem.