Colic in horses: how to recognize an emergency, respond correctly and prevent it

What is colic? The most common emergency in horses

Colic is the umbrella term for abdominal pain in horses [3]. The annual incidence varies by population between 3.5 and 10.6 cases per 100 horse-years [2][6][7][8]. That makes colic one of the most common life-threatening emergencies in equine practice. Keep in mind that colic is a symptom that can have many different causes.

A horse's anatomy makes it especially prone to colic: the gastrointestinal tract, at about 30 meters in length, is only partly suspended freely in the abdominal cavity. The duodenum, cecum and rectum are fixed by mesenteries and ligaments, while the large intestine is freely suspended. This very mobility raises the risk of displacements and twists. The narrowest point is the pelvic flexure in the large intestine, which is where most impaction colics occur. The small stomach (only 7.5–15 liters) is the reason horses cannot vomit: if it is overloaded, a life-threatening stomach rupture is a risk.

Causes: spasm, gas, impaction or displacement

The good news: most colics can be treated with medication and heal without lasting effects. The most common forms of colic are:

Spasmodic colic (spastic colic): The intestinal muscles cramp, often triggered by stress, a sudden change of diet (in German) or a change in the weather. The pain can be severe, but it usually responds quickly to treatment.

Gas colic (flatulent colic): Excessive gas formation from hard-to-digest feed or a disturbed gut microbiota. The intestine bloats painfully.

Impaction colic: Feed material backs up in the intestine, mostly at the pelvic flexure of the large intestine. Causes are dehydration, too little forage, poor dental care or too much sand in the feed.

Sand colic: A less common form in Germany, but regionally relevant, especially on sandy soils. Sand accumulates in the large intestine over months and can cause severe impactions or irritation of the mucous membranes there. A risk factor is sandy pasture or paddock ground, especially when the grass is short.

Displacement and torsion: The intestine shifts out of its normal position or twists. These forms of colic are life-threatening and usually require emergency surgery. Strangulations (cut-off blood supply) are among the most severe forms of colic [5].

Recognizing the symptoms: what you can see

Spotting colic quickly saves lives. The signs vary with the intensity of the pain, but these symptoms should alarm you [3]:

Early warning signs:

• Restlessness, lying down and getting up repeatedly
• Pawing with the front legs
• Looking or kicking at the belly
• Flehmen (raising the upper lip and stretching the neck)
• Refusing food
• Fewer or smaller fecal balls, dry or slimy manure

Clear signs of colic:

• Rolling and uncontrolled roll-overs
• Cold sweat without physical exertion (sign of shock)
• Sawhorse stance or dog-sitting posture: the latter is highly pathognomonic for problems in the proximal small intestine
• Stretched-out neck, severe restlessness or apathy
• Elevated pulse: normal is 28–44/min, over 48–50 = warning sign, over 60 = emergency
• Pale, bluish or reddened mucous membranes
• Absent or greatly reduced gut sounds

Emergency criteria (call the vet immediately, even at night):

• Persistent violent rolling despite movement
• Pulse over 60 beats/min
• Heavy, cold sweating and trembling
• Bluish discoloration of the mucous membranes (cyanosis)
• Collapse or inability to rise
• Dog-sitting posture

Immediate steps: what you can do as an owner

Step 1: Call the vet, always and right away. Every minute counts in severe cases. The prognosis worsens the longer a colic that needs surgical treatment goes untreated [5].

Step 2: Remove feed and water. Keep the horse from eating more or drinking large amounts of water, which can make the situation worse.

Step 3: Stop the horse from rolling violently. Don't generally prevent the horse from lying down, but uncontrolled rolling can lead to self-injury. The old teaching that rolling causes an intestinal twist is considered controversial. More recent studies suggest that horses with an existing intestinal twist roll for relief. In practice: letting the horse lie quietly is okay, but gently stop violent rolling to prevent injury.

Step 4: Lead the horse at a walk in a controlled way. Calm leading (10–15 minutes) can relieve mild spasms. But don't force a severely painful horse to walk.

Step 5: Write down vital signs. Document pulse, respiratory rate, mucous membrane color, temperature and capillary refill time (CRT). Normal values: pulse 28–44/min, respiratory rate 8–16/min, temperature 37.5–38.2 °C, CRT under 2 seconds, mucous membranes pink and moist.

What you should NOT do:

• Don't give any medication without instructions from your vet (pain medication masks clues for the diagnosis)
• Don't give oils or home remedies
• Don't wait around with a “it'll pass” attitude.

Veterinary diagnostics: how the vet finds the cause

The vet starts with a thorough clinical exam: heart and respiratory rate, mucous membrane color, gut sounds, pain level. Targeted follow-up procedures come next [3]:

Rectal exam: The vet palpates the abdominal organs through the rectum. Impactions, displacements and painful sections of bowel can be identified directly.

Nasogastric tube: A tube is passed through the nostril into the stomach. Fluid that has built up in the stomach can be drained (this prevents gastric rupture), and laxatives can be given.

Abdominal ultrasound: Shows thickened bowel walls, fluid accumulation, bowel displacements and motility.

Abdominocentesis: The color, cell count and protein content of the abdominal fluid give signs of inflammation, such as peritonitis, and of circulatory problems.

Blood work: Hematocrit (dehydration), lactate (tissue damage), inflammation markers.

A complete initial work-up typically takes 60–90 minutes and gives a basic assessment of whether medical treatment is enough or emergency surgery is needed.

Treatment: medical or surgical

About 75–80% of colic cases are mild and respond well to medical treatment, and only about 4% require emergency surgery [2]. Depending on the cause, the vet uses:

Pain medication and antispasmodics: Flunixin meglumine or metamizole for pain relief, butylscopolamine for cramps. Buscopan compositum combines butylscopolamine with metamizole, so it relieves both cramps and pain.

Important practical notes:

• Butylscopolamine temporarily raises the pulse by 20–40 beats/min for 20–30 minutes (parasympatholytic effect). Tell the vet on the phone that Buscopan was given.
• Flunixin meglumine masks clinical signs of pain for 8–12 hours. With a colic suspected to be surgical, give no flunixin meglumine before referral to the equine hospital [4]. The hospital needs the true clinical picture for the surgery decision.

Fluid therapy: Intravenous fluids stabilize the circulation and support movement through the intestines.

Laxatives and enemas: Mineral oil (liquid paraffin) or sodium sulfate (Glauber's salt) via the stomach tube for impactions.

Surgery: If conservative therapy does not work or there is a strangulating displacement/torsion, emergency surgery is the only option. Overall mortality in surgically treated colic is about 34%, with an 82% survival rate for nonstrangulating displacements [5]. Every hour counts.

After surgery comes inpatient monitoring for 7–10 days, with perioperative antibiotics for 24–72 hours [9], pain management and gradual reintroduction of feed.

Prognosis: quick action makes the difference

Horses with mild to moderate colic that are treated within the first hours have an excellent prognosis. The overall mortality from colic is 0.5–0.7 deaths per 100 horse-years [2][7][8]. The case fatality rate is 4–13%, depending on the population and access to treatment [2][6][7][8].

The longer the pain lasts, the higher the pulse and the paler the mucous membranes, the worse the outlook without surgical intervention. The first two hours are decisive for your horse's chance of survival.

Prevention: how to reduce colic risk

Colic cannot be prevented completely, but you can lower the risk significantly [1][2]:

• Continuous forage access: Hay ad libitum or spread over several portions throughout the day. Long gaps between meals promote gastric ulcers and impactions.
• Make feed changes slowly: Plan at least 10–14 days. The gut microbiota needs time to adjust.
• Regular dental checks: At least once a year. Sharp tooth edges prevent thorough chewing. In senior horses, a look at the incisors is part of the check too (EOTRH).
• Enough water: At least 20–40 l per day. In winter, offer warmed water or mash.
• Parasite control: Strategic deworming based on fecal sample analysis (in German). Excessive parasite infection is associated with an increased colic risk [1]. Resistance patterns and licensed products are regional. The fecal egg count logic transfers, the product names do not.
• Stress reduction: Changing barns, transport and heavy training loads increase colic risk [2].
• Exercise: Regular turnout and free movement promote gut motility.

Watch high-risk horses especially closely:

• Mares in the first two months after foaling (cecal inversion, large colon volvulus) [1][11]
• Horses that have had colic before (recurrence risk clearly increased)
• Horses with confirmed gastric ulcers (EGUS)
• Horses on long-term NSAID medication (right dorsal colitis) [10]

Bottom line

Colic is the emergency every horse owner fears, and rightly so. But panic doesn't help: spotting it quickly, acting right away and giving the right first aid save lives. Learn the warning signs, know your horse's vital signs and keep your vet's number handy. About 75–80% of colic cases are mild and can be treated conservatively if they are caught in time. And with a well-thought-out feeding and management strategy, you can significantly lower the risk from the start.

Frequently asked questions about colic in horses

This article does not replace advice from your vet.