Why is My Cat’s Tail Twitching?

Cat's tail

Why is my cat’s tail twitching? Often an animated tail tells us our cat is feeling playful and ready to pounce. Other times, it means they’re irritated and ready to give you a swift pawing or nibble if you choose to continue to pet them. Cats use their tails to communicate to each other, too.

Usually, when a cat’s tail twitches, quivers or flickers, it means quite a number of different things depending on the situation. Your cat could be communicating happiness, anger or distress. He or she could also be suffering from muscle tremors if the switching is involuntary.

The height in which a tail is held as well as the shapes it creates tell others a variety of messages: “I’m friendly,” “I want to play,” “I feel unsure about you,” and “Stay away from me”. An uncontrollable quivering tail while a cat is resting, however, is more difficult to dissect.

Since it’s not part of a conversation they’re having with you or another pet, typically movement in the tail while at rest is an unconscious or uncontrollable movement that doctors and veterinarians refer to as fasciculations or muscle tremors.

And while these are completely harmless, they tell a complicated story, as the origin of the muscle quivering could be nothing or could be the result of something as serious as a nervous system disorder.

To better evaluate if the movement in your cat’s tail is normal, it’s best to understand the role the tail plays in cat body language.

Body Language in Cats

Much like dogs, cats use their tails to interact with their environment and send communicative messages to others. However, while a loose, wagging tail in dogs shows they’re happy or excited, it can mean quite the opposite in cats.

It can be difficult to understand what a cat is communicating if you pay attention to only their tail. Usually, other non-verbal cues or environmental factors can help you hone in on their message.

Typically, the best way to determine a cat’s current emotion is to pay attention to the height and speed of their tail.

1. Low, slow twitching – ready to pounce

This may be the tail twitch most are familiar with. A tail hung low with a slow flicking is usually partnered by large, watching eyes or even a crouching stance. This tail movement means they’re ready to pounce.

Usually, we see this tail when they’re playing with other cats or watching birds while perched on a window sill.

2. High, quick twitching – Excited cat

A tail held high can express both excitement and confidence. You may have seen your cat strut through the kitchen with their tail extended into the air. This means they’re extremely comfortable in their environment, and may in fact, even be saying, “I own the room.”

A tail held high like this but combined with a quick tremble or twitch indicates excitement. You may see this tail right before feeding them or when you’re greeted at the front door after a long day at work.

3. Low, quick twitching – irritation

Unlike a low hung tail that’s slowly flicking back and forth, back and forth, a low tail combined with fast twitching expresses not playfulness, but irritation.

If you witness this type of tail-speak while petting a cat, you better remove your hand quick! They’re trying to tell you they’re not feeling a massage right now.

4. Fast flopping or “thrashing” – aggression

What’s referred to as a thrashing tail is a sign of anger and most likely a coming aggression.

This tail may be flopping side to side so quickly, that it makes a pronounced thump on the floor. It’s best to not approach a cat communicating this aggressive message.

See this chart for more:

Cat's tail twitching - what does it mean?
Cat body language. What your cat’s tail could be telling you.

Why would a cat’s tail be twitching when sleeping or lying down?

With over 20 vertebrae in the tail alone, a cat’s tail can bend and move in a variety of ways. And surrounding the bones of the tail are a number of nerves and muscles, which is why your cat will yelp in pain when you accidentally step on their tail.

Since their anatomy allows for the tail to move in a variety of ways and in a variety of positions, it’s not abnormal for tails to flick while a cat is lying down.

In fact, a nice slow flicking of the tail accompanied with lying down and slowly blinking eyes or purring could be a sign of comfort and, if uninterrupted, will usually lead to a cat nap.

Tails moving while a cat is asleep, however, isn’t a sign of intentional communication. However, it’s not necessarily a cause for concern. Just like humans, felines may experience muscle tremors.

Muscle tremors are involuntary and harmless and typically occur at a specific point on the R.E.M. cycle.

However, it’s difficult to tell the difference between muscle tremors and other medical issues, which is why a veterinarian’s diagnosis is important. A few causes to consider if you’re witnessing tail quivering in your cat while they’re resting or sleeping include:

  • A side effect of medication

While prescribed medications help our pets heal after trauma, feel better while in pain, as well as prevent fleas and ticks, these medicines all come with side effects.

Always research and read labels before administering medicine to your cat and if you have questions, call your vet to confirm it could be medication causing the uncontrollable quivering.

  • Deep sleep cycle

R.E.M. is a scientific acronym used to explain the stage of sleep in which rapid eye movements (which is what R.E.M. stands for) occur. Mammals of all shapes and sizes experience R.E.M. cycle, including us, and including felines. During this sleep stage, muscle movement is common.

  • Toxicity or poisoning

You should always keep cleaning supplies and even some types of plants out or reach from your cat. Were they to get into something poisonous to them, muscle twitching would be a side effect.

If you suspect this, call your veterinarian’s office immediately. Even a tick’s bite could cause issues in the nervous system.

  • Injury

Trauma or improper healing of a damaged bone, muscle, or nerve could cause involuntary muscle twitching or quivering.

Localized muscle twitching – meaning you observe the only the tail moving uncontrollably and not other parts of the body – is often the result of injury to that specific area. If your cat recently had their tail pulled by a toddler, this could explain a lot.

  • Genetic

While this is more common in dogs, possibly a result of irresponsible overbreeding, some kittens may be born with overactive muscles or nerves. These are called congenital disorders and while present at birth, it’s possible for the issue not to take form until later in the cat’s life.

  • Nervous system issues

The most serious reason for involuntary muscle or nerve quivering could be the result of a nervous system disease.

  • Metabolic disorder

Another serious medical condition associated with muscles quivering could be the result of low blood sugar or even kidney failure.

Kidney failure in cats is most common when they encounter and ingest poisonous substances, such as household cleaning products or medicines meant for humans.

When a cat’s tail is twitching uncontrollably…

If you’re not a licensed veterinarian, then you should never attempt to diagnose and treat a pet yourself. A misdiagnosis could mean your feline friend’s underlying issues go untreated, which at best, could keep them uncomfortable, and at worst, could be life-threatening.

Due to the fact that certain issues and stimulants may cause muscles to quiver in a cat’s tail, the first thing you should do if you’re witnessing uncontrollable twitching is set up an appointment with a veterinarian.

Do your vet a favor by trying to be as descriptive as possible about what it is you’ve noticed.

Your vet is likely to ask you when you first started noticing the tremors as well as if the cat has suffered any recent trauma or injury to their tail.

If you’re able to catch the involuntary tail movements on camera, then record them and show them to your vet.

If the vet and their medical team believe the tail quivering could be linked to internal trauma to bones, muscles or nerves or a nervous or autoimmune disorder are likely to request one or all of the following:

  • X-Rays, CT scan or MRI
  • Blood work
  • Testing of cerebrospinal fluid
  • Electromyography

When to be worried

While it could be possible all you’re seeing is your cat dreaming, it’s also possible it could be more. You should be worried if involuntary tail quivering is associated with pain.

While cats, like dogs, are excellent at hiding physical pain, there are several cues you can be on the lookout for.

  • Alterations to their routine

Cats thrive on routine. They typically even memorize it. You’ll know this when they come yowling in your ear, letting you know it’s time for dinner. However, with a cat in pain you may start to see them caring less about or changing their routine.

This takes the form in less grooming, over-grooming, less activity or interest in moving around, a lack of appetite or thirst, as well as choosing to use the floor instead of their litter box.

  • Physical changes

The easiest physical changes to spot would include limping, swelling, cuts, or missing fur. There are other signals, however, such as dilated eyes and/or heavy breathing, much like panting.

  • Behavioral changes

While cats are known for their temperamental attitudes, this behavior could escalate if they’re experiencing pain.

If your feline family member is typically more tolerant of being touched and suddenly becomes overtly aggressive or irritated more easily by interaction, you should bring this up to their veterinarian.

List of Sources

  1. https://www.catbehaviorassociates.com/your-cats-tail-what-it-says-about-her-mood/
  2. https://www.catster.com/cat-behavior/cat-tail-wagging-the-meaning-of-different-cat-tail-wags
  3. https://www.petmd.com/cat/conditions/neurological/c_ct_tremors
  4. https://www.merckvetmanual.com/cat-owners/brain,-spinal-cord,-and-nerve-disorders-of-cats/nervous-system-disorders-and-effects-of-injuries-in-cats
  5. https://www.catster.com/lifestyle/cat-tail-5-cool-facts
  6. https://www.petcoach.co/article/skeletal-anatomy-bones-joints-and-muscles-in-cats/
  7. https://www.medicalnewstoday.com/articles/320388.php
  8. https://www.medicinenet.com/tremor/article.htm