Why Is My Dog Shaking or Trembling?

Feeling cold

Dogs Trust calls cold the most common reason for a dog shaking. Shivering is a natural way to regulate temperature. The Kennel Club explains that it is an involuntary response, as the muscles cycle between tightening and relaxing, which generates heat.

Smaller dogs, dogs with thinner coats and slim dogs may shake in the cold more because they lose heat more quickly. If your dog is cold, give them a cosy spot to warm up. A jumper, coat or booties can help dogs that are prone to shivering.

Excitement and shaking off

Shaking with excitement is a normal reaction. It is usually seen in younger dogs and settles when the dog calms down. A full-body shake after play can also help dogs release built-up adrenaline, and dogs shake simply to dry off.

Fear, anxiety and stress

Fear, anxiety or stress can make a dog tremble. Triggers include fireworks, loud noises, thunderstorms, separation anxiety and vet visits. The Kennel Club explains that adrenaline floods the system and gets the muscles ready for action.

Stress shaking usually comes with other clues, such as panting, hiding, ears pulled back, whimpering and the whites of the eyes showing. A "shake off" after a stressful event can also be a stress response.

For an anxious dog, work out the trigger and check your dog is healthy with your vet. Then seek a qualified behaviourist.

Pain

Shivering or shaking is one of the common signs of pain, and dogs are very good at hiding pain. Other clues include seeming down or grumpy, licking the sore area, limping, stiffness and going off food.

Feeling sick

Dogs can shake or shiver when they feel sick or nauseous. Look for lip licking, dribbling or repeated swallowing.

Older dogs and tired muscles

In older dogs, weakening muscles can cause trembling in the legs or body. Leg shaking when standing or walking may point to arthritis pain.

Shaking limited to one area, especially the legs, may also be muscle weakness or fatigue. A long walk or run that your dog is not used to can cause it.

Overheating

A dog may shake from overheating or heatstroke. PDSA lists shaking among the moderate signs of heatstroke. Vets Now says panting that comes with shaking or restlessness can be a potential emergency. Dogs Trust says to call your emergency vet right away if you think your dog may have heatstroke.

Seizures

A seizure can look like shaking. Dogs Trust lists stiffening muscles, reduced mobility, falling over and possible loss of bladder or bowel control. PDSA says most seizures cause full-body convulsions with collapse, jerking and drooling, while some are milder, such as twitching in the face or one leg.

PDSA lists many possible causes of seizures, including idiopathic epilepsy, toxins, head trauma, heatstroke, low blood sugar and liver disease. It says idiopathic epilepsy is the most common cause in dogs between six months and six years old.

Poisoning

Several poisons can cause shaking or tremors. PDSA says signs of chocolate poisoning usually appear within two to four hours but can take up to 12 hours. In severe cases they include fast breathing or panting, shaking, trembling, fever and seizures.

The Kennel Club also lists slug baits that contain metaldehyde, cannabis, some mouldy foods, nicotine, xylitol, macadamia nuts and caffeine. Xylitol is a sweetener found in sugar-free gum, some peanut butters and baking. Blue Cross says xylitol signs typically appear within 30 minutes but can take up to 12 hours.

Slug pellets with metaldehyde have been banned for outdoor sale and use in the UK since 2022, but old stock can still poison pets. Vets Now lists sickness, drooling, wobbliness, severe tremors and convulsions among the signs.

Infection and other conditions

Distemper is a virus that can cause shaking or tremors, along with a runny nose, high temperature, cough, tiredness, sickness and poor appetite. Puppies and young dogs, particularly those that are not fully vaccinated, are at higher risk. It is now rarely seen thanks to vaccination.

Generalised tremor syndrome, also called shaker syndrome, causes head and body tremors. It was first noticed in small white dogs, but any dog can get it. The cause is unknown and thought to be immune-mediated, and signs usually appear in young adult dogs. In many dogs the tremors worsen with excitement or exercise and may ease at rest. A vet has to rule out other causes before diagnosing it, and VCA, a US source, describes the outlook as excellent with veterinary treatment.

The Kennel Club lists less common medical causes, such as kidney failure, inflammatory brain conditions, low blood sugar and low calcium. PDSA adds that low blood sugar seizures are very rare in fit, healthy dogs.

Shaking in puppies

If your puppy is shaking, always speak to your vet. The Kennel Club names causes such as cerebellar hypoplasia, where the part of the brain that controls coordination is poorly developed. It also names hypomyelination, or "shaking puppy syndrome", with signs from about two weeks old.