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