Saddle thrombus in cats – signs and what to do

Updated 2026-09-30 · 1 sources

Based on: PDSA

See a vet now

This is an emergency – contact your vet or the nearest emergency vet right now. A saddle thrombus is a blood clot that blocks blood supply to a cat’s back legs.

What you can do now

  1. Contact your vet or the nearest emergency vet right now.
  2. Note when it started, how often it happens and what else you see.
  3. Take a photo or short video to show the vet.
  4. Let your cat rest somewhere calm.

Don't

  • Do not give any human medicine.
  • Do not wait if it gets worse.

What it is

A saddle thrombus is a blood clot that blocks blood supply to the back legs.[1] Saddle thrombus is a life-threatening emergency.[1]

Signs

  • Severe pain
  • Dragging one or both back legs, or being unable to stand
  • Licking or chewing the affected leg or legs
  • Stiff or firm muscles in the affected leg or legs
  • Affected leg or legs may feel cold
  • Pale paw pads on the affected leg or legs

sudden

Causes and risk factors

  • Heart disease
  • Cancer
  • Hyperthyroidism

How vets treat it

  • Pain relief
  • Hospitalisation
  • Medication

What the experts say

“Severe pain ; Dragging one or both back legs, or being unable to stand ; Licking/chewing the affected leg(s) ; Stiff or firm muscles in the affected leg(s) ; Affected leg(s) may be cold to the touch ; Pale paw pads on the affected leg(s)”

If your pet is struggling to breathe, has collapsed, is having a seizure or can't stand up: go to the nearest vet now.

Not sure how serious it is?

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Common questions

What is a saddle thrombus?

It is a blood clot that blocks blood supply to the back legs. [1][1]

What signs can a saddle thrombus cause?

Signs include severe pain, dragging one or both back legs or being unable to stand, and pale paw pads on the affected legs. [1][1]

Why is it urgent?

It is a life-threatening emergency, so contact your vet immediately if your cat shows symptoms. [1][1]

Sources

  1. PDSA

How this page was made: written with the help of AI from the sources below, then checked claim by claim against those sources. Urgency levels follow OkPaw’s fixed safety rules. It is guidance, not a diagnosis. How we write our pages

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