Dog Shaking and Trembling: Causes and When to Worry

A shaking dog is one of the most common reasons pet owners search online at 2am. The good news: most trembling is harmless. The important news: some of it isn't. Here's how to tell the difference.

Common and Harmless Causes

Cold

The most frequent cause. Small, lean, or short-coated dogs (Chihuahua, Whippet, Italian Greyhound, Greyhound) get cold quickly. A warm blanket or coat usually resolves this in minutes.

Excitement

Many dogs tremble when greeting you, seeing a leash, or anticipating food. This is physiological — adrenaline activating the muscles — and completely normal.

Fear or Anxiety

Thunderstorms, fireworks, vet visits, strangers, or new environments can trigger visible shaking. Watch for accompanying signs: tucked tail, flattened ears, panting, hiding.

Old Age

Senior dogs commonly develop a mild tremor from muscle loss, arthritis, or benign essential tremor. It's typically chronic, mild, and often confined to the back legs.

Medical Causes That Need Attention

Pain

A dog in pain — from a disc herniation, acute arthritis, or injury — often trembles at rest. Look for protective posture, reluctance to move, limping, or vocalizing when touched.

Hypoglycemia (Low Blood Sugar)

Most common in small dogs, puppies, and diabetic dogs. Shaking is accompanied by weakness, confusion, and in severe cases, seizures. This is a medical emergency.

Poisoning

Xylitol (in sugar-free gum and candy), chocolate, grapes, caffeine, and some medications cause acute trembling with vomiting and altered consciousness. Treat as an emergency.

Epilepsy

Epileptic seizures involve rhythmic whole-body trembling, loss of consciousness, and a confused post-ictal phase. Film the episode if you can and see the vet the same day.

White Shaker Dog Syndrome

An idiopathic generalized tremor syndrome, most common in small white dogs (Maltese, West Highland White Terrier, Bichon Frisé). It responds well to corticosteroids.

Addison's Disease

Adrenal insufficiency causes episodic weakness, trembling, and collapse. Diagnosed via blood cortisol and ACTH testing.

Distemper

Canine distemper can cause muscle twitches and tremors in unvaccinated dogs. Keeping vaccinations current prevents this.

Emergency Signs

Go to an emergency vet immediately if the shaking is combined with:

• Loss of consciousness
• Repeated vomiting or bloody diarrhea
• Difficulty breathing
• Inability to stand
• Known or suspected toxin exposure
• Temperature extremes (very cold or hot to touch)

How to Prepare for the Vet Visit

• Record a short video of the trembling — rhythm, duration, localized or full-body
• Note when it started and what the dog was doing
• Check whether the dog had access to any unusual food, plants, or chemicals
• Log everything in Purzi and use the vet-visit report feature to organize it

Frequently Asked Questions

Why does my dog shake after a bath?

It's cold — wet fur loses heat quickly. Dry your dog promptly, especially small or short-coated breeds.

My dog trembles in their sleep. Is that a seizure?

Most likely not. Twitching, paddling, or mild tremors during sleep are normal REM sleep activity. A true seizure typically wakes the dog and is followed by a confused state.

Can anxiety make a dog shake constantly?

Yes — chronic anxiety can cause persistent trembling. If your dog shakes in multiple everyday situations, address the anxiety with a behaviorist and/or vet, not just management.