Pegasus Health Gastri-Kalm®

Made in the UK
Pegasus Health Gastri-Kalm® from Pegasus Health
2 kg(30 day)£42.95
6 kg(92 day)£104.95

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Active ingredients per 65 g serving
Apple pectin 5 g
Calcium carbonate 20 g
Liquorice root 5 g
Magnesium carbonate 10 g
Seaweed (fucus) 5 g
Slippery elm (inner bark) 5 g
Soy lecithin 10 g
Threonine 5 g
GRAND TOTAL 65 g

Stomach (gastric) ulcers are common in all types of horses, especially hard working performance horses and those kept intensively. Prevalence rates of up to 90% (in racing thoroughbreds) have been reported, and all breeds and types can be affected.

Pegasus Gastri-Kalm® has been formulated to support and maintain a healthy stomach, and to aid natural healing after ulcers. It contains antacids to mop up excess acid, stomach-soothing and healing herbs and soluble fibres, and the amino acid threonine for stomach lining support.

Management practices should support good stomach health, with plenty of forage, as much grass turnout as possible, limited starchy or sugary concentrate feed, and free access to water. Hard-working horses should be allowed access to forage or given a small meal of alfalfa chaff half an hour before exercise to help protect their stomach.

All hard working horses should be given extra stomach support, to help them deal with the pressures of their training regime. Feed Pegasus Gastri-Kalm® to all hard working horses at risk of gastric ulcers, and to any who are at risk from other factors such as drug treatments or restricted forage intake.

Gastri-Kalm® contains these active ingredients:

  • Apple pectin
  • Calcium carbonate (antacid)
  • Liquorice root
  • Magnesium carbonate (antacid)
  • Seaweed fucoids (Ascophyllum nodosum)
  • Slippery elm inner bark (Ulmus fulva)
  • Soy lecithin
  • Threonine (amino-acid)

Gastri-Kalm® should be fed to all horses at risk of gastric ulcers including all those in hard work. The daily serving should be split between meals. Horses at risk of ulcers should be fed plenty of fibrous forage, limited concentrate feed, very low starch and should be turned out to pasture as much as possible.

Feed to horses and ponies:

  • With or at risk of gastric ulcers (including hard–working performance horses)
  • With a poor appetite who show signs of discomfort
  • Given non-steroidal anti-inflammatory drugs
  • On very restricted forage e.g. obese/weight-loss resistant/laminitic


  g per day
Scoops per day
Heavy horse (700 kg and over) 130 2
Horse (400-700 kg) 65 1
Pony (up to 400 kg) 32.5 0.5





For best results, split between 2 feeds approximately 12 hours apart.

A 2 kg tub fed at 65 g per day will last 30 days.

Gastric ulcers in horses
The prevalence of gastric ulcers in mature horses has been reported as between 58 to 93% of a given population, and racehorses are particularly affected. Horses are prone to gastric ulcers due to modern feeding and management practices. Their stomachs are designed to take in small quantities of fibrous forage almost continuously, with plenty of saliva produced by chewing, and they have an almost continuous production of acid. Without free access to forage, their stomach acid can build up, causing damage to stomach tissue and, eventually, ulcers. In addition, the action of galloping causes acid splashing on the vulnerable, non-glandular upper part of the stomach, due to the increased pressure in the abdomen. Performance horses are often exercised intensively, fed limited forage and high levels of starchy concentrate, with limited or no time spent turned out with other horses, and these are known to be risk factors. As soon as forage is restricted, starchy grain-based diets are fed and horses exercised and kept intensively, they are at risk of gastric ulcers.

Some of the non-steroidal anti-inflammatory drugs used in horses increase the risk of gastric ulcers, so they should be used with care.

Horses can have ulcers in both the non-glandular upper part of the stomach, and the lower, glandular part, although most are found in the non-glandular area, near the border with the glandular. The term EGUS (equine gastric ulcer syndrome) is a term used to describe ulcers in the bottom of the throat, both areas of the stomach and the upper part of the small intestine. Gastric ulcers cause pain and discomfort and can lead to poor performance and poor utilisation of the diet. Very severe ulcers can cause stomach rupture. Effective drug treatments are available, but they do not alter the cause of the problem and should ideally only be used short term.

Prevention of gastric ulcers in horses
Horses should be managed in such a way to reduce the risk of gastric ulcers, with plenty of forage, limited starch intake, forage available before hard work, socialization and ideally, turnout to pasture. Continuous access to forage is best for stabled horses, but where it has to be restricted, it should be fed in several portions to avoid more than 4 hours fasting. Horses at risk should also be given free access to water both in the stable and at pasture, which seems to help reduce the risk.

All horses at risk of gastric ulcers should be fed a stomach-supporting supplement to help their stomach health.


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