Involuntary Muscle Trembling in Cats

Involuntary muscle trembling, or fasciculations, describes a condition in which muscles tremble, twitch, or spasm uncontrollably. This can occur in cats and other companion animals for various reasons. Muscle trembling normally occurs in response to irritants or emotions and is not necessarily related to any medical condition. It is also possible that trembling or twitching might be caused by a genetic condition and is untreatable, but not dangerous. In some cases, fasciculation occurs as a sign of another disease or disorder. Some medical conditions that cause muscle trembling can be severe and may be life-threatening. If muscle trembling continues, seek medical attention for your cat. 

Involuntary muscle trembling can take many forms. The trembling can occur rapidly with the movements happening in quick succession, or it may occur at a slower pace often described as twitching. The fasciculations may also be localized, meaning it only affects a certain part of the body. Localized trembling or twitching in cats most commonly affects the head or hind legs. The muscle trembling could also be general, meaning it affects the entire body. In both localized and generalized trembling the movement may be persistent or episodic. Additional, seemingly unrelated, signs may also be observed depending on the underlying cause of the trembling. 

Signs Include:

• Uncontrolled trembling or twitching
• Sensitivity to touch
• Repetitive pawing or scratching
• Pain and vocalizations that might be related to pain

Various conditions may cause involuntary muscle trembling as a sign or there may be no discernable cause. It is possible for the twitching or trembling to simply be part of your pet’s normal response to certain stimuli in their environment or to be an emotionally-triggered response. Involuntary trembling can also be a primary condition, rather than a sign of something else. Some of the potential causes for involuntary muscle trembling in cats and other companion animals include:

• Nervous system disorder
• Kidney failure
• Certain medications
• Toxicity or poisoning
• Injury or trauma
• Strong emotional responses like excitement, fear, or anxiety
• Deep or REM sleep stages
• Itchiness from dry skin, mites, or fleas
• Low blood calcium
• Hypoglycemia or low blood sugar
• Vitamin or mineral deficiencies
• Electrolyte imbalances
• Rabies
• Seizure disorders like epilepsy
• Feline hyperesthesia or rolling skin disease
• Congenital or genetic conditions
• Pain
• Weakness
• Certain cancers, especially those affecting the nervous system or muscles

Various diagnostic techniques may be needed to determine what is causing the trembling or twitching. Your veterinarian will begin with a full physical examination and medical history. You should discuss any signs you have observed, including how frequent the trembling occurs and which portions of the cat’s body are affected. If the fasciculation is episodic and does not occur all the time, a video recording of the trembling may aid your veterinarian in forming a diagnosis. Veterinary staff might take samples of your cat’s blood and urine for laboratory analysis. The blood sample will be tested for blood cell counts, biochemistry and electrolyte panels, or antibodies that might indicate an infection. Urinalysis and analysis for proper kidney function will be checked using the urine sample. Additional diagnostic methods, including x-rays or other imaging techniques, may be needed to diagnose your pet properly. 

The treatment method used by your veterinarian will be determined by their diagnosis of the underlying cause of the trembling. These treatments can vary widely depending on the condition causing the trembling and may include surgery, medications, or other methods. If no cause is determined, medication may be prescribed to aid in a reduction of the trembling. Some of the common treatments used for muscle trembling include:

Muscle Relaxants

Drugs in this category are designed to relax muscles, which may help reduce or eliminate the tremors. This treatment must be properly dosed for your pet’s size and physical condition to reduce the risk of side effects. 

Supplementation 

If a deficiency or imbalance is the cause of the trembling, your veterinarian may recommend supplementation to restore the cat’s nutrient balance. 

Anti-Depressants or Anti-Anxiety Medications

If the cause is determined to be psychosomatic, medications designed to improve mental state may be recommended. Proper dosing is needed with this type of treatment to minimize the risk of side effects. 

The prognosis for recovery will depend on the underlying cause of the muscle trembling. Trembling may never go away in some cases, but it is still possible for your pet to live a normal life. If the underlying cause is treatable, most cats will make a full recovery as long as they respond well to treatment. Certain causes of involuntary muscle trembling may respond less to treatment, and in these cases, recovery may not be possible. In any case, your care and support will benefit your pet. 

Involuntary muscle trembling can be expensive to treat. If you suspect your cat has involuntary muscle trembling or is at risk, start searching for pet insurance today. Brought to you by Pet Insurer, Wag! Wellness lets pet parents compare insurance plans from leading companies like PetPlan and Trupanion. Find the “pawfect” plan for your pet in just a few clicks!

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