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Sand colic is a term for abdominal pain in horses caused by the ingestion of sand.
Depending on the geographic region, five to thirty percent of all colic cases are caused by sand or sediment accumulation in the gut. [1][2][3]
Sand colic typically occurs in dry areas with poor vegetation growth. When horses forage, sand particles and other sediments (such as silt and gravel) are ingested and may remain in the large colon for long periods. [1]
Sand enteropathy or impaction occurs when sand accumulation damages the large intestine, leading to inflammation of the colon wall, distress or complete bowel obstruction. Without medical intervention, impaction colic can be fatal.
Acute colic is a serious condition that requires medical attention. If your horse forages in a sandy region and presents clinical signs of sand colic, contact your veterinarian immediately.
Sand Colic in Horses
When horses ingest sand particles, some of the sediment is cleared via bowel movements. However, sand can begin to accumulate in the ventral colon and cecum of the horse, negatively impacting gut motility (the movement of food through the intestines).
Sand accumulation can lead to weight loss, diarrhea, constipation, stomach distension, poor performance and acute colic.
In extreme cases, obstipation (severe or complete constipation) from blockages may occur, and intestines can rupture. [4]
It is unknown how much sand needs to accumulate in the digestive tract to cause clinical signs of impaction. [5] Signs of sediment accumulation vary depending on the size of the horse, and some horses display no symptoms at all. [6]
Clinical Signs
After ingesting large amounts of sand, horses may exhibit typical colic symptoms, such as: [7]
- Lack of appetite
- Distressed or anxious behavior
- Pawing at the floor
- Looking at or biting at the sides of the belly
- Lying down, standing up, rolling over
- High heart rate (over 64 bpm) or other changes in vital signs
If your horse displays signs of colic, contact your veterinarian immediately for urgent care. All forms of colic should be treated as a medical emergency.
Why do Horses Eat Sand?
Sand colic is usually attributed to incidental sand ingestion that occurs when horses are foraging in sandy regions. However, some horses may intentionally ingest sand or soil at pasture, a practice known as geophagia.
This behavior may indicate a nutritional deficiency (such as a lack of selenium or sodium in the diet) or boredom in horses. [6][8] However, further research is needed to understand the factors that cause geophagia.
Both wild and domesticated horses have been observed to return to specific locations to ingest soil repeatedly. They may be seeking out certain minerals in the soil, but site selection does not seem to correlate with soil mineral content. [8]
Risk Factors for Sand Colic
Several factors increase a horse’s risk of sand colic, including feeding on the ground or in sandy paddocks, housing horses on sandy soils or keeping horses on low-quality pastures. [1]
Horses turned out in sandy paddocks or pastures may ingest soil while searching the ground with their lips for forages. Sand colic is most common in the southern United States (i.e. Arizona and Utah), where the soil is dry and forages are more scarce.
Horses with restricted access to forages or hay could be more likely to colic due to a lack of fiber in the diet. [7] Fiber is critical for gut motility and clearing ingested sand and soil from the digestive tract.
What's your top priority with your horse's health?
What's your top priority with your horse's health?
Some breeds, such as the Quarter Horse, Shetland Pony, Miniature Horse and Finnhorse, are believed to be more susceptible to sand colic. This may be related to a higher appetite in these breeds. [6]
Diagnosis
Your veterinarian will conduct a differential diagnosis to rule out other conditions that may be causing symptoms of sand colic. [6]
Clinical presentation of sand accumulation may mimic other diseases or conditions, such as laminitis, tying-up (rhabdomyolysis) or pneumonia. [7]
Horses may experience poor performance, which can be mistaken for Equine Gastric Ulcer Syndrome (EGUS) and treated as such.
Auscultation of the Abdomen
Abdominal auscultation can accurately diagnose sand colic by using a stethoscope and listening for sand sounds in the gut.
Abdominal sounds indicating sand accumulation are gritty and resemble the sound of waves crashing on a beach. [1][6][9]
Sand sounds vary in intensity and duration, depending on the amount of sand accumulated, with large accumulations resulting in more noise. Sand sounds are believed to occur when greater than 6.3 – 10.5 kg of sand accumulates in the colon. [6]
Many veterinarians can identify abnormal gut sounds associated with large amounts of sand in the colon. Coarse sands may produce more identifiable noises, making diagnosis easier.
Fecal Sand Sedimentation
Fecal sand sedimentation is a reliable diagnostic tool for sand colic or impaction in horses.
However, results can be highly variable between individual horses and fecal samples. Some horses with large sand loads do not excrete sand.
Follow these steps to conduct a fecal sand sedimentation test at home on your horse: [5]
- Gather a few manure balls from a fresh pile and place them in a plastic bag (avoid using manure that has touched the ground)
- Fill the plastic bag halfway with water and squeeze the manure sample to create a mixture
- Hang the bag by a corner and allow the sample to settle over several hours
Horses with a moderate to severe sand load in the digestive tract will have a substantial amount of sand settling in the corner of the bag.
If a bag is unavailable, a fecal sand test can be conducted by mixing feces with water in a bucket. [1]
Note that healthy horses who live in sandy areas may pass small amounts of sand in their feces without signs of physical pain. Small sand loads in the gut are common in some geographical areas and are rarely cause for concern.
If a horse shows signs of colic or diarrhea and is passing noticeable sand in their feces, call your veterinarian immediately for examination and diagnosis.
Some horses may also demonstrate clinical signs of colic without passing any sand.
Abdominal Radiography & Ultrasound
The best method to determine the severity of colonic sand accumulations is abdominal radiography. [3][5] Sand and other sediments have a distinct shadow in a radiograph, and grading systems can be used to determine the size of the accumulation. [6]
Radiography can also be used to assess the effectiveness of treatments or supplements for evacuating sand from the gut. [5]
Ultrasonography is generally accurate when ruling out sand accumulation, although it has limited use when diagnosing positive tests. [6] This makes ultrasound an accurate screening tool with limitations for diagnosis. [3]
Treatment
The prognosis for sand colic varies as horses tolerate sand accumulation differently. Early medical intervention is key to successful treatment when dealing with colic.
Many mild cases of sand colic are treated with a combination of nonsteroidal anti-inflammatory drugs (NSAIDs), mineral oil, magnesium sulfate (epsom salts), dioctyl sodium sulfosuccinate and psyllium. [3]
Acute Sand Colic
To reduce the sand load in the gut, the colicky horse must first be stabilized. Feeds should be withheld until any emergency impaction is resolved.
Once symptoms of acute colic have subsided, the affected horse can undergo treatment to reduce sand accumulation in the gut. Treatment for acute sand colic includes: [6]
- Pain & inflammation control (NSAIDs)
- Fluid & electrolyte administration
- Mineral oil administration
Some horses may require stronger painkillers than NSAIDs alone, which can be administered by a veterinarian.
Clinical signs should begin to resolve 2-3 days after the initial treatment, and the horse’s sand load should be diminished after 3-4 weeks of treatment. [10] Horses with impaction that do not improve with medication may require surgery to alleviate blockages.
Psyllium
Psyllium is one of the only recognized non-invasive treatments for sand accumulation in the gut. [1] Although studies have shown mixed results, this supplement may improve sand clearance in horses. [1][11]
Psyllium husks are derived from the Plantago ovata plant and are available in powdered or pelleted form. This is the main ingredient in Metamucil®, which is used to alleviate constipation in humans.
The husks are a source of soluble fibre that resembles bran and acts as a laxative in the colon. [3]
When psyllium comes into contact with water in the digestive tract, it swells and develops a gel consistency. This fibrous solution eases the passage of sand and increases fecal output. [6]
Feeding psyllium is sometimes recommended by veterinarians as a preventative measure for sand accumulation. Psyllium is thought to stimulate intestinal motility, induce peristalsis (contractions in the gut) and shorten the passage time for feed through the digestive tract. [4]
After feeding psyllium, horses with sand accumulation will excrete jelly-like droppings that contain moderate amounts of sand. Always ensure that supplements are being used as intended and directions and instructions are being followed carefully.
Probiotics & Prebiotics
Research shows that combining probiotic, prebiotic, and psyllium treatment may increase fecal sand clearance and gut motility in horses with sand accumulation. [3]
This combination may also reduce irritation and inflammation associated with sand accumulation, although further research is needed.
Surgery
Surgery for sand accumulation is typically conducted on an emergency basis if the horse has severe impaction or cannot pass sand with the help of treatment.
Impaction usually occurs at the pelvic flexure, which is an area of the colon that folds back on itself at a sharp angle. [12]
Sand and feedstuffs can get stuck in this area, fully obstructing the intestine. Sand is manually removed from the intestine during surgery through an incision.
Colic surgery is expensive and is not usually a planned procedure. Owners should always have an emergency plan for their horses.
Prevention
Sand ingestion cannot be entirely prevented, but sand accumulation and risk for colic can be reduced with management practices.
Ensure your horse has adequate access to good-quality hay. Fiber-rich forages help move sand through the digestive tract. [6]
Provide your horse with constant access to fresh, clean water to prevent feed impaction in the intestines and promote sediment movement through the gut. Adequate hydration is important for gut motility and preventing colic.
Feed your horse 1 – 2 ounces of plain loose salt and provide free-choice loose salt at all times. Salt promotes water intake and electrolyte balance.
In rare cases, horses sensitive to sand accumulation or colic may need to be confined to a smaller sand-free paddock or muzzled to prevent sand ingestion. However, this is a last resort and other preventative measures should be implemented first.
Raised or Contained Feeders
Horses should be fed forages off the ground or from raised feeders to prevent sand from accumulating in the feedstuff. [7]
Hay and concentrates should be contained in feeders (hay nets, feed racks, etc.) and prevented from falling onto the sandy ground. [6][7]
Rubber mats can be placed under feeding containers or forages in a paddock or at pasture to prevent accidental sand ingestion.
Feeding Psyllium
Horses susceptible to or at high risk of sand accumulation may be fed a preventative psyllium supplement daily for one week each month. [10]
This practice may prevent large amounts of sand from accumulating in the gut by promoting regular excretion. [3]
Digestive Supplements
Sand accumulation in your horse’s gastrointestinal tract can disrupt the microbiome, cause inflammation in the intestines, and affect nutrient absorption.
If your horse tends to accumulate sand in the gut or has a history of colic, feed an equine digestive supplement to support healthy gut function and the immune system.
Mad Barn’s Optimum Digestive Health is a pelleted supplement that supports hindgut health and microbiome balance with 100% natural ingredients.
This comprehensive blend of probiotics, prebiotics, enzymes, yeast and nucleotides improves nutrient uptake and helps reduce the risk of digestive dysfunction and colic.
Consult with our equine nutritionists for further ways to support your horse’s gut health and to prevent or promote recovery from sand colic.
Frequently Asked Questions
Here are some frequently asked questions about sand colic in horses:
Sand colic is abdominal pain caused by sand or sediment building up in a horse’s intestines. Horses living in dry, sandy regions can accidentally swallow sand while grazing or eating hay off the ground. Over time, accumulated sand may irritate the colon, slow gut movement, or create dangerous blockages that lead to diarrhea, weight loss, poor performance, or severe colic symptoms requiring urgent veterinary care.
Signs of sand colic include pawing, rolling, loss of appetite, anxious behavior, looking at the belly, and repeated lying down or getting up. Some horses also develop diarrhea, weight loss, dull performance, or sensitivity around the abdomen. Horses with severe impactions may show elevated heart rates above 64 beats per minute and worsening pain that does not improve without veterinary treatment.
Horses in sandy areas do not always develop sand colic because many pass small amounts of sediment naturally through normal manure output. Risk increases when large amounts of sand accumulate faster than the gut can clear them. Limited forage access, feeding directly on sandy ground, dehydration, and poor gut motility can all increase the chance of clinically significant sand accumulation.
Some horses intentionally eat dirt or sand through a behavior called geophagia. Researchers believe this behavior may relate to boredom, low forage intake, or nutritional imbalances involving minerals such as sodium or selenium. Horses may repeatedly return to certain areas to consume soil even when mineral levels vary. Ongoing soil eating warrants a closer look at forage availability, diet balance, and management routines.
Certain horses appear more prone to sand colic, including Quarter Horses, Miniature Horses, Shetland Ponies, and Finnhorses. Increased appetite or aggressive foraging behavior may raise sand intake in these breeds. Horses kept on sandy paddocks, sparse pasture, or dry southern soils also face greater risk. Feeding practices and forage access usually influence sand accumulation more strongly than breed alone.
Horses can carry significant sand accumulation without showing obvious symptoms for long periods. Some horses continue eating and behaving normally even with moderate sand loads in the colon. Others develop mild diarrhea, subtle weight loss, or reduced performance before acute colic appears. Lack of visible symptoms does not rule out sand accumulation, especially in horses living on sandy soils or dry pasture.
Veterinarians diagnose sand colic using physical exams, gut sounds, fecal sedimentation tests, radiographs, and ultrasound imaging. Sand accumulation often creates gritty abdominal sounds that resemble waves moving on a beach. Radiographs provide the clearest picture of sand buildup and can measure severity. Fecal sand testing at home may also reveal sediment settling at the bottom corner of a plastic bag or bucket.
Amount of sand needed to cause dangerous impaction varies greatly between horses. Some develop clinical signs with relatively small accumulations, while others tolerate larger amounts for longer periods. Veterinary exams often detect gritty abdominal sounds when roughly 14 to 23 pounds, or 6.3 to 10.5 kilograms, of sand collect in the colon. Early treatment remains important because severe impactions can become life-threatening.
Psyllium may improve sand clearance by forming a gel-like fiber mass that moves sediment through the digestive tract. Veterinarians commonly use psyllium as part of treatment plans for sand accumulation and mild impactions. Horses receiving psyllium often pass jelly-like manure containing visible sand. Research findings remain mixed, but psyllium continues to be one of the most widely used non-invasive options for sand management.
Severe sand colic can require emergency surgery when medications and supportive care do not relieve intestinal blockage. Large accumulations often lodge near the pelvic flexure, where the colon bends sharply and feed material can become trapped. During surgery, veterinarians manually remove impacted sand through an incision in the intestine. Surgical treatment is expensive and usually performed only when obstruction becomes life-threatening.
Feeding hay directly on sandy ground increases risk of accidental sand ingestion during normal eating and foraging behavior. Horses often pick up sediment while searching for dropped forage with their lips. Raised feeders, hay nets, feed tubs, and rubber mats reduce contact between feed and sandy soil. Good-quality forage also supports gut motility, which helps move ingested sediment through the intestines more effectively.
Water intake affects sand colic risk because hydration supports normal gut movement and reduces feed impaction in the intestines. Horses with poor water intake may struggle to move sand and feed material through the digestive tract efficiently. Constant access to clean water, along with adequate dietary fiber and loose salt intake, promotes healthy manure output and supports regular sediment clearance from the colon.
Summary
Sand colic develops when ingested sand or sediment accumulates in the gut, leading to impaired motility, discomfort, or obstruction. Horses in dry, sandy environments are at higher risk, especially when forage is scarce or feeding occurs on bare ground. Diagnosis and response vary widely, making early veterinary assessment essential for safe management and recovery.
- Clinical signs may include weight changes, diarrhea, or typical colic behaviours
- Diagnostic options include auscultation, fecal sediment testing, and abdominal imaging
- Treatment approaches range from NSAIDs and fluids to mineral oil or psyllium
- Preventative strategies rely on forage access, raised feeding, hydration, and monitoring
References
- Rood, K. A. & Tebeau, C. Sand Colic: Risk Factors, Detection, Treatment and Prevention. All Current Publications. 2011.
- Walesby, H. A. et al. Equine sand colic. Compendium on Continuing Education for the Practicing Veterinarian - North American Edition. 2004.
- Landes, A. D. et al. Fecal Sand Clearance is Enhanced with a Product Combining Probiotics, Prebiotics, and Psyllium in Clinically Normal Horses. J Equine Vet Sci. 2008.
- Hotwagner, K. & Iben, C. Evacuation of sand from the equine intestine with mineral oil, with and without psyllium. J Anim Physiol Anim Nutr. 2007. View Summary
- Hassel, D. M. Evaluation of Fecal Sand Clearance in Horses with Naturally Acquired Colonic Sand Accumulation With a Product Containing Probiotics, Prebiotics and Psyllium. J Equine Vet Sci. 2020.View Summary
- Niinistö, K. & Sykes, B. W. Diagnosis and management of sand enteropathy in the horse. Equine Vet Educ. 2021.
- Loving, N. Colic: Updates and Prevention. American Association of Equine Practitioners (AAEP). 2016.
- McGreevy, P. D. et al. Geophagia in horses: a short note on 13 cases. Appl Anim Behav Sci. 2001. View Summary
- Ragle, C. A. et al. Abdominal Auscultation in the Detection of Experimentally Induced Gastrointestinal Sand Accumulation. J Vet Intern Med. 1989. View Summary
- Stewart, A. J. Sand Enteropathy in Horses. MSD Manual Veterinary Manual. 2022.
- Mienaltowski, M. J. et al. Psyllium supplementation is associated with changes in the fecal microbiota of horses. BMC Res Notes. 2020. View Summary
- Specht, T. E. & Colahan, P. T. Surgical treatment of sand colic in equids: 48 cases (1978-1985). J Am Vet Med Assoc. 1988.
