1. If the animal is not conscious, assess the ABCs and perform CPR as required.
  2. Do not force a collapsed animal to stand or walk as this may worsen signs.
  3. Seek immediate veterinary attention.


Collapse is the loss of an animal’s ability to support their body weight without assistance and may involve loss of consciousness.


Signs depend on the underlying cause, but animals may exhibit:

  • Weakness
  • Pain
  • Distress
  • Inability to stand or walk without assistance
  • Loss or urinary or fecal continence
  • Panting
  • Difficulty breathing (dyspnoea)
  • Pale gums or blue-tinged gums (cyanosis)
  • Obvious signs of haemorrhage
  • Vomiting
  • Diarrhoea
  • Loss of consciousness


There are multiple causes of collapse which can be divided into categories.

  • Cardiovascular: inadequate circulation of the muscles and nervous system (may occur with heart failure, pericardial effusion, cardiac arrest or severe haemorrhage, such as may occur with a ruptured organ or tumour)
  • Respiratory: inadequate oxygenation of the blood and tissues (may occur with choking, severe lung disease, and disorders affecting the oxygen carrying capacity of red blood cells)
  • Metabolic or endocrine: usually occurs due to deficiency of metabolic fuel for the body, or electrolyte losses/deficiencies (examples include low blood glucose, low calcium or low potassium; and diseases such as Addison’s disease)
  • Neuromuscular: reduced or disturbed nerve conduction (this may occur with disorders such as tick paralysis, snake envenomation or myasthenia gravis)
  • Neurological: disorders of the central or peripheral nervous system which is responsible for normal mentation and limb function (for example, head or spinal cord trauma)
  • Orthopaedic: failure of the skeleton and joints to support weight and allow ambulation. This can be acute, for example in the case of trauma, or chronic, for example in the case of arthritis.


Veterinary care depends on the underlying cause. Your veterinarian will perform a full physical examination and assess your pet. Additional diagnostic tests may include blood and urine tests, a venom detection test, blood pressure measurements, cardiac monitoring, x-rays or ultrasound, joint-taps, airway examination (potentially under sedation or anaesthesia), aspiration of fluid from a body cavity (including the sack of tissue around the heart or pericardium) and specific testing or advanced imaging for other conditions.


Macintire DK, Drobatz KJ, Haskins SC and Saxon WD (2006) Manual of small animal emergency and critical care medicine. Oxford: Blackwell.

Reiss AJ (2007) Aural haematoma. In Clinical Veterinary Advisor Dogs and Cats ed. Etienne Cote. St Louis: Mosby Elsevier, pp225-226.