Severe Colic and New Treatments

Generally, the population of horses that develop severe colic includes the ones that don’t respond to the veterinarian’s initial treatment. Almost all severe colics start as mild colics that are simply left too long.

No account yet? Register

Addressing your horse’s clinical signs early is the key.

Severe colic is characterized by intractable pain and signs of septic shock, which is any type of loss or poor distribution of blood supply caused by bacteria or their toxins. The bacterial toxin we most commonly think about is endotoxin, so horses are usually called endotoxemic when their gum color changes, the time it takes for the capillaries of the gums to refill after pressure from a finger (called capillary refill time) increases, and the heart rate remains elevated despite treatment for pain.

However, there are many different bacteria and toxins that can trigger the same reaction.

Septic shock is the horse’s body mounting a massive immune response to bacterial toxins that, in horses with colic, have escaped from the intestine. In order to escape, the gut lining or barrier has to be broken down, and this happens when the bowel is strangulated (the intestine has become twisted or entrapped in an area of the abdomen that pinches off the blood supply).

If a horse with a strangulating obstruction of the intestine is not attended by a veterinarian and taken to surgery, it will die from the body’s response to bacterial toxins that escape from the intestine. That is why endotoxemia has been so extensively researched

Create a free account with to view this content. is home to thousands of free articles about horse health care. In order to access some of our exclusive free content, you must be signed into

Start your free account today!

Already have an account?
and continue reading.


Written by:

Anthony Blikslager, DVM, PhD, Dipl. ACVS, is a professor of equine surgery and gastroenterology at North Carolina State University’s College of Veterinary Medicine. His research interest is gastrointestinal physiology in horses, studying the mechanisms of injury and repair in the gut with the clinical outlook of enhancing recovery of horses with colic.

Related Articles

Stay on top of the most recent Horse Health news with

FREE weekly newsletters from

Sponsored Content

Weekly Poll

sponsored by:

Has your veterinarian used SAA testing for your horse(s)?
92 votes · 92 answers

Readers’ Most Popular

Sign In

Don’t have an account? Register for a FREE account here.

Need to update your account?

You need to be logged in to fill out this form

Create a free account with!