Experienced and professional animal trainer provide their insights in answering this question :
A. It could be a vestibular or neurological problem or possibly a toxic reaction. Without more information it is impossible to say. I would recommend contacting your vet or emergency vet straight away and discuss it in more detail.

How to Identify Common Pet Problems ?

Our sources include academic articles, blog posts, and personal essays from experienced pet care professionals :

In many cases, your dog may tremble for everyday reasons like anxiety or muscle weakness from old age. “But, if it is happening often and they are showing any other abnormal signs, they should definitely be seen by a veterinarian to rule out other potentially life-threatening diseases,” Matejka says.
Potential causes include inner/middle ear infections, intoxication, strokes, tumors, infectious or inflammatory diseases (meningitis), idiopathic vestibular disease (also called “old dog” vestibular syndrome), or other less likely causes.
The inner ear is where the sense of balance originates, and when it is damaged, that balance can be lost. Infections, inflammation, tumors, and trauma to this sensitive area can cause your dog to be shaky and uncoordinated.
Is your dog losing balance, shaking, or falling over? Your dog`s loss of balance could be the result of a serious medical issue, such as poisoning, stroke, injury, or an infection. Today, our Winston-Salem vets explain why you should head to an animal hospital right away if your dog is experiencing balance issues.
Symptoms can include collapsing, jerking, stiffening, muscle twitching, loss of consciousness, drooling, chomping, tongue chewing, or foaming at the mouth. Dogs can fall to the side and make paddling motions with their legs. They sometimes poop or pee during the seizure. They are also not aware of their surroundings.
Some signs of a stroke in dogs include a head tilt, circling, loss of balance, and unusual eye movements. If you think that your dog is having a stroke, don`t delay getting them to the vet for diagnosis and treatment. Treatment is mostly supportive, and it`s important to treat any underlying causes.
In the case of a stroke, your pet`s brain sends incorrect signals to their body. For example, your pet may not be able to respond to your spoken directions. Instead, he may move in a directionless fashion and seem to be walking in circles. He may appear as though he is drunk and be unable to walk in a straight line.
Your dog could be suffering from a sensory dysfunction called Ataxia that results in a loss of coordination in the head, limbs, or rear end. There are three kinds of ataxia seen commonly in dogs: cerebellar, sensory and vestibular. Cerebellar ataxia occurs when the cerebellum is damaged.
Some of the signs of parvovirus include lethargy; loss of appetite; abdominal pain and bloating; fever or low body temperature (hypothermia); vomiting; and severe, often bloody, diarrhea. Persistent vomiting and diarrhea can cause rapid dehydration, and damage to the intestines and immune system can cause septic shock.
If your dog begins to shake uncharacteristically, develops other illness signs, or you suspect they ingested a toxin, you should seek urgent veterinary care through your primary veterinarian or a local emergency veterinary facility.
This can happen due to mobility-reducing health conditions, surgery recovery, or lack of use in aging. Arthritis in your dog`s back legs may cause the muscle in your dog`s legs to atrophy. Not so coincidentally, arthritis is another condition that could cause your dog`s legs to become shaky and weak.
Shaking limbs can signify neural distress, poisoning, kidney failure, distemper, pain, or weakness. You must speak with your veterinarian or neurologist right away.
Signs of a Simple Focal Seizure

Dogs experiencing a simple focal seizure could display one or more of the following signs: Hallucinations (Your dog may bark, growl or moan at nothing, bite at the air or behave fearfully for no apparent reason) Signs of vision or hearing changes. Fur standing up.

Petit Mal Seizure (Absence Seizure): This type of seizure is rare in dogs; the term “petit mal” should not be used to described a partial or mild generalized seizure in dogs. A dog having a petit mal seizure may tremble, arch his back or shake his head, have difficulty standing, and/or drool.
Symptoms of an intestinal blockage begin

Once the obstruction has occurred, clinical signs may develop such as vomiting, diarrhea, abdominal pain and loss of appetite. As soon as you notice these clinical signs, it`s time to see your veterinarian for an evaluation.

Affected dogs show signs 30 minutes to 4 hours after ingesting the poison. Initially affected dogs become anxious and have an elevated body temperature. Panting is usually seen. Progressively they become worse and staggery.
Limb shaking TIAs are a rare form of TIAs that present as involuntary movements and often confused with focal motor seizures. [1–6] This distinction, however, is crucial as this form of TIA is often an indicator of severe carotid occlusive disease and patients are at high risk of future stroke.
The most common extracranial causes are hypoglycemia, hypocalcemia, hyperthermia, hypothyroidism, liver disease, or ingested poisons such as caffeine, and chocolate. Intracranial causes of seizures are diseases that cause either structural or functional changes inside the dog`s brain.
A stroke happens when blood flow to the brain is interrupted. A seizure occurs when the brain experiences a surge of electrical activity.
Some of the most common reasons for your dog`s shaking & shivering are cold, excitement, stress & anxiety, seeking attention, pain or illness, and old age. It`s important to recognize the difference between normal shaking vs. signs of a seizure.
The last few days before your dog passes you may notice: extreme weight loss, a distant look in their eyes, a lack of interest in anything, restlessness or unusual stillness, a change in the way that your dog smells, and a changed temperament.
Diarrhea or projectile diarrhea: The stool will become very watery and is often made up of “old blood” in the intestinal tract. Limb weakness and shaking.
Canine influenza is a viral infection that primarily affects dogs, but can sicken cats, too. Currently, two strains have been identified in the United States: H3N8 and H3N2.
The first sign of parvo for puppies is often lethargy, lack of appetite, and a fever. Canines will begin to suffer from vomiting and diarrhea as the virus progresses, and can experience dehydration and a high heart rate as a result.

Relevant Questions and Answers :

the most relevant questions and answers related to your specific issue

Q. I was walking my dog with my wifeand he was acting normal when my wife bent over pick up a paper he tucked his tale ran about 20 feet and locked up
ANSWER : A. So he was startled. Next time, carry high value treats with you on your walks and feed them periodically for good behavior. Encourage him to walk alongside, you encourage him to allow you to bend over here and there throughout your walk. Do not make any sudden movements, and makes sure your dog is comfortable throughout the entire walk. Using treats will help him make positive associations with being walked by your wife and you.

Q. What can I do to help our Lab stop pulling on the leash when we go for a walk? I have tried different techniques but after 2 1/2 years she still pulls
ANSWER : A. POST TWO:
In the mean-time, while you’re working on building up that attention indoors, you should be using a front hooking harness outdoors on your walks. This will eliminate your girls pulling power. The Sensible http://www.softouchconcepts.com/index.php/product-53/sense-ible-harness and the Sensation http://www.softouchconcepts.com/index.php/product-53/sense-ation-harness harness are the best front hooking harnesses on the market because they do not have the martingale loop on the front of the harness (which can cause the dog to yo-yo during walks).

Lastly, I’d just like to add that dogs sniff the ground during walks for added mental stimulation. If your dog isn’t allowed to sniff the ground, the walk isn’t nearly as fun or tiring. When you are practicing attention on your walks, make sure it’s in short, small bursts. Attention for a few steps, back to sniffing for several steps, attention for a few steps, sniffing for a few minutes.. etc.

Q. Why does my poodle sneeze only while walking never while sleeping, eating, playing. Her nose is runny too. She doesn’t show any other symtoms. Help.
ANSWER : A. Your dog may be sensitive to something she encounters while on her walks that she is not exposed to at any other time. Try a different route to see if the sneezing occurs less or at a different part of the walk, try walking her at a different time of day and make a note of where it is and what she’s doing when she sneezes. If the symptoms persist, it’s worth getting her checked by your vet for any irritation or foreign substance found in her nasal passages.

Q. My 1 year old great Pyrenees will not walk on the leash she stops and jumps around on the leash and when I try to walk her she just sits down.
ANSWER : A. At one year, she is right in the middle of canine adolescence which is when new fears can show up. She needs positive reinforcement and luring to teach her leash walking is a good thing. You can take some special, tasty treats that she doesn’t get regularly for leash walking time only. Use these treats to lure her forward a little bit at a time. Don’t pull or force her or it will become a big, negative experience to only reinforce her discomfort. Keep it light, positive, and fun. You will likely only get a short distance the first few days, but within a few weeks you should be able to increase that and help her overcome her fear about it.

Q. My puppy refuses to walk outside on the leash. This only happens when we’re outside… Is it stubbornness or fear?
ANSWER : A. It is never stubbornness. Dogs are not stubborn, they can’t be. Dogs do not generalize well, and dogs display fearful behavior that appears to be stubbornness. Absolutely NEVER force this dog to walk outside when he is uncomfortable with doing so.. the more you force him to do it, opposition reflex – the more he will resist. The more he resists and is forced into it, the less he learns about being comfortable, and the more he becomes fearful of you and of the situation.

What you can do is carry extremely high value treats outside with you. Things like cooked white meat chicken, cooked fish, turkey pepperoni, turkey bacon, diced ham, mozzarella cheese sticks – all cut up into tiny little pea-sized pieces. You can also use peanut butter in a squeeze tube. First, put on the leash indoors and begin feeding him the treats. Help him make positive associations with having the leash put on. Then, take the leash off, and start over in 10min. Put the leash on, feed treats, walk to the door, open the door, feed treats, close door, take off leash. Start over in 10min. Put on leash, feed treats, go to door, feed treats, open door, feed treats, go outside, feed tons of treats and praise. Keep Titus in his comfort zone. If he doesn’t want to go far, just feed him tons of treats where he IS comfortable going. Make sure everything is calm/happy/positive. I bet in a week of doing this, he will be happy with walk further and further all of the time. If ever he is uncomfortable, feed him lots of treats for being a brave boy, and then turn around and go back home. It’s all about keeping him in his comfort zone.. it’s all about remaining within his threshold and never forcing him to feed uncomfortable.

This is very common for puppies. The world is scary! It’s brand new to them, and it’s up to you to make their interactions and discoveries positive, happy, calm, and to never force them into anything.

Q. How many minutes or hours should I play with my 3 month old puppy per day?

How long should I walk him per day?

ANSWER : A. Play with him as much as you like but as soon as he goes off to sleep or goes to his quiet space then it is important to leave him alone until he comes back to play again. Walking depends upon his size and breed. If you can do 2-3 shorter walks a day that will be good, as he gets older you can do longer walks.

Q. How do I teach my dog to sit still enough and not move his head while I clip on the gentle leader?
ANSWER : A. Most dogs HATE the gentle leader, and it’s not at all surprising. Would you want something foreign on your face? It’s an uncomfortable training tool, and no dog enjoys wearing it. If you are looking to have your dog behave better on-leash, you should consider tossing out that gentle leader, and using a front hooking harness like the Sensible http://www.softouchconcepts.com/index.php/product-53/sense-ible-harness, or the Sensation http://www.softouchconcepts.com/index.php/product-53/sense-ation-harness harness. These harnesses will eliminate the pulling power of your dog, and put you in control in a positive, and gentle way. Any time your dog pulls, he is redirected until he is facing you. You can practically walk your dog with your pinky.

I dislike the gentle leader because it can cause neck injuries in an avid puller/lunger. You also can’t ever hook a long-lead to the gentle leader and allow your dog to run around because it would break his neck. Another thing I dislike about it, is it discourages sniffing the ground during walks. When your dog attempts to sniff, and the leash is short, his nose is redirected upwards. When you trip on the leash, the head is jerked around and the nose is directed upwards. Sniffing during walks is extremely important. Sniffing = mental stimulation, which will tire your dog out more during your walks. The more your dog lags, or forges, the less he can sniff the ground, and the more frustrated he becomes.

If you’re dead set on using the head halti.. you should be using treats to hold his attention. Place the head halti on the floor, reward him for sniffing it, pick it up, treat him, put it near his face, treat him, lure his nose through the loop, lots of treats, take the head halti off, more treats, lure his nose through again, more treats. Take baby steps going forwards AND backwards so the “game” of getting the halti on isn’t always getting more difficult.

Q. Shaking uncontrollable and wobbly when walking and confused
ANSWER : A. It could be a vestibular or neurological problem or possibly a toxic reaction. Without more information it is impossible to say. I would recommend contacting your vet or emergency vet straight away and discuss it in more detail.