Symptom guide

Why Is My Dog Shaking or Trembling? Causes and What to Do

Cold, fear, pain, nausea and poisoning can all make dogs shake. How to tell what's normal, what to do and when trembling is an emergency.

Updated October 2026 · 6 min read · By the Hushku editorial team · 2 sources

See a vet within 24 hours. Emergency if with weakness, collapse or possible poisoning

Short answer

Dogs shake when they're cold, excited, frightened or in pain, and small breeds shiver easily. Shaking is an emergency if it comes with weakness, vomiting, collapse or difficulty walking, if your dog may have eaten a toxin, or if it looks like a seizure (falling over, paddling legs, not responding).

Key facts

Cold, excitement, fear, pain and nausea are common causes of trembling.
Shaking with weakness, vomiting or collapse, or after eating a toxin, is an emergency.
A seizure usually involves loss of awareness; one lasting over 5 minutes is an emergency.
Small and thin-coated dogs shiver more in the cold.

This guide is general information, not a diagnosis. If your pet seems unwell, or you're worried, call your vet.

Overview

Shaking and trembling are common and often harmless: think of a Chihuahua shivering on a cold morning or a dog quivering with excitement before a walk. But trembling is also a sign of pain, nausea, fear and poisoning, so it's worth looking at what else is going on.

Trembling or seizure? During trembling your dog stays aware and responds to you. In a seizure, dogs usually lose awareness, may fall onto their side, paddle their legs, drool, chomp, or lose control of their bladder or bowels. Time it and call your vet; a seizure lasting more than 5 minutes, or several in a row, is an emergency.

Go to a vet now if you see

Shaking with vomiting, weakness, collapse or wobbliness
Your dog may have eaten something toxic
A seizure lasting more than 5 minutes, or more than one in 24 hours
Shaking with a high temperature, heavy panting or after being in the heat

Common causes

1. Cold
Usually mild
Small, thin-coated and older dogs lose heat quickly. A coat and warm bed help.
2. Excitement
Usually mild
Some dogs tremble with anticipation. It stops once the excitement passes.
3. Fear and anxiety
Usually mild
Fireworks, thunderstorms, vet visits and car journeys. Look for tucked tail, pinned ears, panting and hiding.
4. Pain
Needs a vet
Back, neck and joint pain often cause trembling, sometimes with a hunched posture or reluctance to move.
5. Nausea
Needs a vet
Dogs often tremble, drool and lick their lips when they feel sick.
6. Poisoning
Serious
Chocolate, xylitol, some mouldy foods, slug bait and some medicines cause tremors. This is an emergency.
7. Generalised tremor syndrome
Needs a vet
A condition causing whole-body tremors in young dogs, first noticed in small white breeds. Treatable by a vet.
8. Old age and weakness
Needs a vet
Older dogs can tremble in the back legs from weakness or arthritis.

What you can do at home

Warm a cold dog gradually with a blanket or coat.
For fear, give a safe hiding place and stay calm; comforting your dog won't 'reward' fear.
Keep a diary: when it happens, how long it lasts and what came before. A video helps your vet.

When to see a vet

Any emergency sign: go now
Trembling without an obvious cause, or that keeps happening
Trembling with signs of pain or a change in behaviour
Fear-related trembling that affects daily life (ask about anxiety treatment)

Prevention

Keep toxins out of reach
Use coats for small or thin-coated dogs in cold weather
Prepare for fireworks with a safe den, background noise and, if needed, vet-prescribed medicine

Free tools for this

Sources

We check guides against veterinary sources and update them when guidance changes. How we write and review.

Questions.

Why is my dog shaking and panting?

Often fear, pain, excitement or overheating. If panting is heavy and your dog is hot, weak or wobbly, treat it as possible heatstroke and call a vet.

Why does my old dog's back legs shake?

Weakness from muscle loss, arthritis or nerve problems are common causes. Ask your vet about pain relief and exercise to maintain muscle.

Key facts

Overview

Go to a vet now if you see

Common causes

1. Cold

2. Excitement

3. Fear and anxiety

4. Pain

5. Nausea

6. Poisoning

7. Generalised tremor syndrome

8. Old age and weakness