Involuntary Muscle Trembling in Dogs

Tremors in Dogs

Tremors are involuntary, rhythmic and repetitive muscle movements that alternate between contraction and relaxation, usually involving to-and-fro movements (twitching) of one or more body parts. The tremors may be rapid, or they may be slow vibrations, and they can occur in any part of the body. Tremor syndrome usually affects young-to middle aged dogs, and has been known to primarily affect white colored dogs, but a variety of hair-coat colors have been found to be affected as well.

There are some dog breeds that are believed to be predisposed to tremors, including chow chows, springer spaniels, Samoyeds, Weimaraners, Dalmatians, Doberman pinschers, English bulldogs and Labrador retrievers. Dogs that are prone to this condition are referred to as “shaker dogs.”

Symptoms and Types

Involuntary tremors involving any body part may be seen in an affected dog. The tremors may be localized or generalized. Localized cases usually affect the head or hind limbs.

Causes

• Idiopathic (unknown)
• Genetic
• Trauma or injury
• Congenital – present at birth
• As a side-effect of certain drugs
• Severe weakness or pain
• In concurrence with kidney failure
• Lower than normal levels of glucose in the blood (hypoglycemia)
• Toxicity – chemical or plant based
• Inflammation
• Nervous system disease

Diagnosis

Your veterinarian will perform a complete physical exam on your dog after taking a complete medical history, including a background history of the symptoms and the time of onset, and possible incidents that might have led to this condition. Routine laboratory examinations include a complete blood count, biochemistry profile, urinalysis and electrolyte panel.

If brain disease is the primary cause of the tremors, the laboratory tests are usually found to be normal. In metabolic diseases, the biochemistry profile may indicate lower than normal levels of glucose (hypoglycemia), lower than normal levels of calcium (hypocalcemia), and abnormal kidney functions.

Other diagnostic tests will include X-rays, computed tomography (CT-Scan), and magnetic resonance imaging (MRI), especially in cases where the pelvic limbs are affected. These tests may reveal abnormalities in the posterior portion of the spinal cord and vertebrae. In some animals, cerebrospinal fluid, or CSF, is also taken for further testing. The results will vary depending on the primary disease underlying the external symptoms.