Published on
Last updated on
2 min read

Key takeaways

Collapse is identified when a horse suddenly drops to the ground, possibly losing consciousness in the process.

  • There may be no obvious trigger, and causal factors are varied including neurological diseases, heart conditions, infections, and injury
  • A collapsing horse may cause injury to themselves or those around them, and is always considered a medical emergency
  • Diagnostics include a detailed history, bloodwork, a neurological exam, and diagnostic imaging
  • Treatment targets the underlying condition
Are you concerned?

Connect with a vet to get more information about your pet’s health.

Book an online vet

A closer look: Collapse in Horses

Collapse is uncommon, and may be caused by a number of underlying conditions. Some, such as certain neurological conditions, may be life-threatening. Falling horses also pose a risk to those around them, and if a horse has collapsed they are unsafe to ride until examined by a veterinarian. Emergency medical attention is always indicated.

Possible causes

Risk factors

Collapse does not vary in presentation beyond the duration of an episode, which does not always equate to severity. Any advanced disease may result in collapse as it progresses towards end of life. Since horses can not survive for long periods of lying down, and because it is associated with severe and advanced disease, collapse is always an emergency.

Horses that have recently collapsed are not safe to ride until cleared by a veterinarian. Human handlers should take additional precautions around a horse at risk of collapse, as a falling horse can crush and severely injure handlers and other nearby animals.

Testing and diagnosis

Veterinarians usually see a horse after they have collapsed. Providing them with details of the episode assists in diagnosis. Items to note if possible during the episode include

  • When collapse happened
  • How long it lasted
  • Recent changes in horse’s management or routine
  • Frequency of episodes if there have been more than one
  • Level of consciousness during an episode

Diagnostics include:

  • Physical exam
  • Neurological exam
  • Electrocardiogram
  • Bloodwork
  • Diagnostic imaging, including X-rays of the head
  • Specific testing for infectious agents such as viruses

Treatment depends on the underlying cause.

Similar symptoms

Associated symptoms


Erica Larson - Writing for The Horse
Allison Stewart, BVSc(hons), MS, Dipl. ACVIM, ACVECC - Writing for The Horse
Michelle Abraham Linton BSc BVMS DACVIM LAIM - Writing for PennVet
No Author - Writing for Horse Side Vet Guide

Our editorial committee

Our medical review team is responsible for validating and maintaining the quality of our medical information.