Why Is My Dog Shaking? Cold, Fear or Pain

When a dog shakes, many owners immediately worry it's sick. In fact, trembling has many causes, from harmless ones like cold or excitement to serious ones like pain or poisoning. The key is to look at the situation and any other signs to decide whether to watch and wait or head to the vet.

Common, less worrying reasons for shaking

Cold

Short-coated, small, young and senior dogs, and dogs fresh from a bath, shiver easily in cold weather or under a fan or air conditioner. Shivering from cold stops once the dog is dried, warmed and settled somewhere out of the draft.

Excitement

Some dogs tremble when their owner comes home, or when a walk or meal is about to happen. This comes with tail wagging, bouncing and bright eyes, and stops when the dog calms down.

Fear and stress

Fireworks, thunder, car rides, new places or strangers can make a dog shake. It usually comes with a tucked tail, flattened ears, lip licking, yawning, panting, hiding or clinging to you. The shaking stops when the scary thing passes.

Shaking during sleep

Small leg twitches, fluttering eyelids and soft whimpers during sleep usually mean your dog is dreaming. If it wakes normally when you gently call its name, there's nothing to worry about.

When shaking is a sign of illness

• Pain: dogs with belly, back or joint pain, or an injury, often tremble, move stiffly, hunch, refuse to lie down or cry out when touched. See our related article on signs your dog is in pain.
• Fever or infection: shaking with lethargy, loss of appetite, a warm dry nose and fast breathing.
• Nausea: shaking with drooling, constant lip licking, swallowing and vomiting.
• Poisoning: substances such as chocolate, caffeine, human medicines, insecticides, and some mushrooms or plants can cause muscle tremors and seizures.
• Low blood sugar: common in small-breed puppies that miss meals, along with weakness, wobbliness and drowsiness.
• Neurological or hormonal disease: some conditions cause ongoing tremors of the head or whole body. Distemper can also cause muscle twitching.
• Old age: senior dogs may tremble in the hind legs from gradual muscle weakness or joint pain. Don't dismiss it as "just age"; your veterinarian can help your dog feel more comfortable.

What to observe

When your dog is shaking, calmly note the following. This information is very useful to your veterinarian:

1. The situation: is it cold, noisy, are there strangers, did your dog just ride in a car or have a bath?
2. Where the shaking is: whole body, only the hind legs, only the head, or one muscle group?
3. How long: a few minutes and then gone, repeated several times a day, or continuous?
4. Is your dog alert: does it respond to its name, follow you with its eyes, stand up? A true seizure usually involves loss of awareness, drooling, foaming and loss of bladder control.
5. Other signs: appetite, toileting, vomiting, coughing, limping, a tense belly.
6. What your dog might have eaten: a raided trash can, dropped pills, rat bait, chewed houseplants.

If you can, take a short video while your dog is shaking. Many episodes happen only at home and are over by the time you reach the clinic.

What to do at home

• If it's cold: dry your dog, wrap it in a towel and move it somewhere warm and out of drafts.
• If it's fear: take your dog to a quiet room, draw the curtains and play soft music. Stay close, speak gently, don't scold and don't force your dog out of its hiding spot.
• Never give your dog human painkillers. Many are highly toxic to dogs, including common ones. Use any medicine only as directed by your veterinarian.
• If your dog has a seizure: move objects away, keep your hands away from its mouth, don't try to hold it down, and time the seizure.

When to see a vet

• Shaking with vomiting, diarrhea, loss of appetite, lethargy or fever.
• Shaking with signs of pain: crying out when touched, a hunched back, a hard swollen belly, refusing to lie down.
• Suspected poisoning, or you know your dog just ate something harmful: go now, don't wait.
• A seizure, loss of consciousness, a seizure lasting several minutes, or several in a row: this is an emergency.
• A small-breed puppy that is shaky, weak or drowsy after missing a meal.
• Shaking that lasts for days, keeps recurring without a clear reason, or gets worse.
• Shaking after a fall or being hit by a vehicle, even if your dog looks fine on the outside.