Colic is a broad term for abdominal pain in horses and is the leading cause of death in domesticated horses after old age. It is not a single disease but a clinical sign that can result from dozens of underlying conditions, ranging from mild gas distension to life-threatening intestinal strangulation. Every horse owner should be able to recognize the signs of colic and understand when to call the veterinarian, as early intervention dramatically improves outcomes.

Overview

The equine gastrointestinal tract is uniquely vulnerable to colic. Horses have a relatively small stomach (cannot vomit), a long small intestine, and a voluminous large intestine with multiple flexures and a freely mobile large colon that can displace or twist. Major categories of colic include:

  • Gas/spasmodic colic — The most common type; caused by gas distension or intestinal spasm. Usually resolves with medical treatment.
  • Impaction colic — Firm, dehydrated ingesta blocks the intestinal lumen, most commonly at the pelvic flexure of the large colon or the cecum.
  • Displacement colic — The large colon shifts from its normal position (left or right dorsal displacement, nephrosplenic entrapment).
  • Torsion/volvulus — The intestine twists on its axis, cutting off blood supply. This is a surgical emergency.
  • Strangulating obstruction — A segment of bowel loses blood supply due to lipoma pedunculation, herniation, or intussusception. Requires emergency surgery.
  • Colitis/enteritis — Inflammation of the intestinal wall from infection (Salmonella, Clostridium), sand ingestion, or other causes.

Causes & Risk Factors

  • Abrupt changes in feed type, quantity, or schedule
  • Inadequate water intake or dehydration
  • Heavy parasite burden (particularly small strongyles and tapeworms)
  • Dental problems leading to poor feed mastication
  • Sand ingestion from eating off sandy ground
  • Stress (transport, competition, change in routine)
  • Recent anesthesia or surgery (post-operative ileus)
  • Pedunculated lipomas (fatty tumors on a stalk), especially in older horses
  • Coastal Bermuda grass hay and other poorly digestible forages

Symptoms

Signs of colic range from subtle to violent depending on the type and severity:

  • Pawing at the ground
  • Turning the head toward the flank (looking at the belly)
  • Stretching out as if to urinate without producing urine
  • Lying down and getting up repeatedly
  • Rolling (may become violent with severe pain)
  • Sweating without exercise
  • Reduced or absent gut sounds on auscultation
  • Elevated heart rate (resting rate above 44 bpm suggests significant pain)
  • Reduced or absent fecal output
  • Distended abdomen
  • Depression, lethargy, and anorexia
  • Lack of interest in food or water

A horse with persistent, unrelenting colic signs or a heart rate above 60 bpm requires emergency veterinary evaluation. Do not administer Banamine before calling your veterinarian, as it may mask the severity of the condition.

Diagnosis

  • Physical examination — Heart rate, respiratory rate, mucous membrane color, capillary refill time, gut sounds, and digital pulse assessment
  • Rectal palpation — Allows the veterinarian to feel for impactions, displacements, distended bowel, and other abnormalities
  • Nasogastric intubation — A tube passed through the nose into the stomach to check for gastric reflux (indicates small intestinal obstruction) and to administer fluids or mineral oil
  • Abdominal ultrasound — Identifies distended loops of small intestine, free peritoneal fluid, thickened bowel wall, and other findings
  • Abdominocentesis (belly tap) — Sampling peritoneal fluid to assess for strangulation (elevated protein, cell count, or discoloration)
  • Bloodwork — PCV/TP, lactate levels, and electrolytes help assess systemic status and guide prognosis

Treatment & Medications

Medical Management

  • Flunixin meglumine (Banamine) — The first-line NSAID for colic pain. Administered intravenously or orally (paste). Never give intramuscularly, as it can cause fatal Clostridial myonecrosis at the injection site.
  • Xylazine — An alpha-2 agonist sedative/analgesic used for moderate to severe colic pain. Provides rapid relief but short duration (20-30 minutes).
  • Butorphanol — An opioid analgesic often combined with xylazine for visceral pain control.
  • Buscopan (N-butylscopolammonium bromide) — An antispasmodic that relieves smooth muscle spasm; particularly useful for spasmodic colic.
  • Nasogastric intubation with mineral oil and/or water — Used for impaction colic to lubricate and hydrate the impacted ingesta.
  • Intravenous fluid therapy — Critical for rehydrating impactions and supporting cardiovascular function.
  • Lidocaine IV infusion — A prokinetic and analgesic used in hospitalized horses with ileus or post-operative recovery.

Surgical Treatment

Surgery is indicated when medical therapy fails to resolve pain, when nasogastric reflux is persistent, when rectal palpation or ultrasound reveals strangulation or displacement requiring correction, or when peritoneal fluid is grossly abnormal. Colic surgery involves exploratory laparotomy (celiotomy) under general anesthesia with correction of the underlying lesion. Survival rates for colic surgery are approximately 75-85% for non-strangulating lesions and 50-75% for strangulating lesions when performed promptly.

Prognosis

  • Gas and spasmodic colic: Excellent prognosis with medical management (greater than 95% recovery)
  • Simple impaction: Good prognosis with aggressive fluid therapy (greater than 90%)
  • Large colon displacement: Good prognosis with medical or surgical correction
  • Strangulating obstruction: Guarded to fair; depends on duration of ischemia and length of bowel affected
  • Early veterinary intervention is the single most important factor in colic outcome
  • Post-colic management includes gradual reintroduction of feed, monitoring for recurrence, and addressing underlying risk factors

Frequently Asked Questions

Should I walk my colicking horse? Light hand-walking can help distract a mildly painful horse and may encourage gut motility, but do not exhaust the horse. If the horse wants to lie down quietly, that is acceptable. Prevent violent rolling, which can increase the risk of intestinal torsion.

Can I give Banamine before the vet arrives? Discuss this with your veterinarian in advance and follow their emergency protocol. A single dose of oral Banamine paste may be appropriate in some situations, but giving it intravenously (injectable form orally is an option) or intramuscularly carries risks. Masking pain can also complicate the veterinarian’s assessment.

How can I prevent colic? Maintain a consistent feeding schedule, provide constant access to clean water, make feed changes gradually over 7-14 days, maintain a regular deworming program based on fecal egg counts, ensure good dental care, and minimize stress.

How do I know if my horse needs surgery? Your veterinarian will determine this based on pain severity and response to analgesics, presence of nasogastric reflux, rectal palpation findings, ultrasound, and peritoneal fluid analysis. Persistent uncontrollable pain, a heart rate that remains elevated despite treatment, and abnormal peritoneal fluid are common surgical indicators.

This information is for educational purposes only and does not replace professional veterinary advice. Colic can be life-threatening. Contact your equine veterinarian immediately if your horse shows signs of colic.