Page 834 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

Gastrointestinal system: 4.2 The lower gastrointestinal tr act 809

VetBooks.ir Table 4.7 Options for the treatment of gastric ulceration

DRUG CLASS DOSE ROUTE INTERVAL COMMENT
Ranitidine H2 antagonist 6.6 mg/kg p/o q6–8 h Oral administration is preferable. Inconsistent
efficacy as a therapeutic
1015 mg/kg i/v q8 h
Omeprazole Proton-pump antagonist 2–4 mg/kg p/o q24 h Best evaluated treatment
1–2 mg/kg p/o q24 h Preventive therapy
4 mg/kg i/m q7 d Novel long-acting formulation
Sucralfate 20–40 mg/kg p/o q6–8 h Adjunctive therapy for EGGD. Not recommended
as a sole treatment
Misoprostol PGE analogue 5 μg/kg p/o q12 h Potentially useful alternative for EGGD

descriptive terminology is preferred for EGGD. In moderate to severe cases, performance should cease
Identification of severe EGUS in a foal should during the treatment period. Possible stressors should
prompt an evaluation of gastric emptying because be addressed.
gastric outflow problems can produce severe ulcer-
ation. A positive response to therapy is supportive Prognosis
of a diagnosis of EGUS but does not differentiate The prognosis is excellent if appropriate treatment is
ESGD from EGGD. When diagnosed based on provided, although recurrence is likely if long-term
response to treatment, gastroscopy should ideally be management changes are not made. Perforation of
performed prior to the discontinuation of therapy. EGUS carries a grave prognosis. Routine antiulcer
prophylaxis of sick or hospitalised horses is contro-
Management versial. It is debatable whether sick horses, particu-
A combination of drug therapy and management larly foals, respond adequately to antiulcer therapy
changes is important. A variety of drugs are available and there is additional concern that raising gastric
for the treatment of EGUS (Table 4.7). Omeprazole pH may be a risk factor for the development of infec-
is the best evaluated drug and the relative efficacy of tious colitis, as has been shown in humans.
other treatments is less clear. H2 antagonists may be
useful but may be more effective at relieving clinical GASTRIC DILATION
signs than promoting full healing. Antacids have not
been shown to be beneficial; however, they may tem- Definition/overview
porarily ameliorate clinical signs during early treat- Distension of the stomach by gas or fluid can cause
ment with H2 antagonists or proton-pump inhibitors. signs of colic and potentially result in gastric rupture.
Treatment duration depends on lesion type and
disease severity. Typically, treatment of at least Aetiology/pathophysiology
21–28 days should be given. Ideally, gastroscopy Gastric dilation may be primary or secondary.
should be repeated prior to cessation of treatment. Primary dilation occurs as a result of excessive gas
Horses with severe or recurrent EGUS that are not production following ingestion of highly fermentable
taken out of training may benefit from preventive feed material or excessive consumption of water fol-
therapy following treatment. lowing exercise. Secondary dilation occurs as a result
Management changes are also critical. Horses of an obstructive small-intestinal lesion, excessive
should be fed a hay- or pasture-based diet and should intestinal secretion or disrupted intestinal motility.
have roughage available at all times. Turnout is pre- The stomach distends with ingested fluid, stomach
ferred. Concentrates should be decreased or withheld. gas and reflux of fluid from the small intestine.