Changes

====Proton-pump inhibitors (PPIs)====

====Proton-pump inhibitors (PPIs)====

PPIs irreversibly bind to the H+K+-ATPase proton pump of the parietal cell and block the secretion of hydrogen ions.  These agents are more effective than H2 antagonsists as their action is receptor-independent,<ref name="EGUC">The Equine Gastric Ulcer Council (1999) Tutorial Article: Recommendations for the diagnosis and treatment of equine gastric ulcer syndrome (EGUS).  ''Equine Vet Educ'', 11(5):262-272.</ref> blocking the final pathway of acid secretion and they have a prolonged effect allowing for once-daily dosing.((Brown and Rees 1994). Papich 1993, Sanchez)  '''Omeprazole (Gastroguard™)''', a subsituted benzimidazole, is currently the only PPI licensed for use in horses.  At a dose rate of 4mg/kg per day omeprazole has proven effective in reducing the severity of gastric ulcers in Thoroughbred horses in active race training (Vatistas 1999) and no adverse effects have been observed.  The paste formulation is easy to administer and generally well accepted by horses.  Omeprazole has demonstrated efficacy in the resolution ofboth naturally-occurring and NSAID-induced gastric ulcers in horses.(103.104 in Sanchez)  A single dose has also produced an increase in gastric pH in clinically ill neonatal foals<ref>Javsicas, L.H, Sanchez, L.C (2008) The effect of omeprazole paste on intragastric pH in clinically ill neonatal foals.  ''Equine Vet J'', 40(1):41-4.</ref> and has contributed to ulcer healing in neonates.<ref>MacAllister, C.G, Sifferman, R.L, McClure, S.R ''et al.'' (1999) Effects of omeprazole paste on healing of spontaneous gastric ulcers in horses and foals: a field trial.  ''Equine Vet J Suppl'', 77-80.  In: Sanchez, L.C (2010) 'Diseases Of The Stomach' in  Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref>  A potential concern is that altering gastric pH may encourage bacterial overgrowth.  Thus further work is needed to evaluate the long-term safety of omeprazole in horses and particularly, foals.<ref>Vatistas, N.J, Snyder, J.R, Nieto, J, Thompson, D, Pollmeier, M, Holstes, J (1999) Acceptability of a paste formulation and efficacy of high dose omeprazole in healing gastric ulcers in horses maintained in race training.  ''Equine Vet J Suppl'', 29:71-76.</ref>

PPIs irreversibly bind to the H+K+-ATPase proton pump of the parietal cell and block the secretion of hydrogen ions.  These agents are more effective than H2 antagonsists as their action is receptor-independent,<ref name="EGUC">The Equine Gastric Ulcer Council (1999) Tutorial Article: Recommendations for the diagnosis and treatment of equine gastric ulcer syndrome (EGUS).  ''Equine Vet Educ'', 11(5):262-272.</ref> blocking the final pathway of acid secretion and they have a prolonged effect allowing for once-daily dosing.((Brown and Rees 1994). Papich 1993, Sanchez)  '''Omeprazole (Gastroguard™)''', a subsituted benzimidazole, is currently the only PPI licensed for use in horses.  At a dose rate of 4mg/kg per day omeprazole has proven effective in reducing the severity of gastric ulcers in Thoroughbred horses in active race training<ref name="Vatistas">Vatistas, N.J, Snyder, J.R, Nieto, J, Thompson, D, Pollmeier, M, Holstes, J (1999) Acceptability of a paste formulation and efficacy of high dose omeprazole in healing gastric ulcers in horses maintained in race training.  ''Equine Vet J Suppl'', 29:71-76.</ref> and no adverse effects have been observed.  The paste formulation is easy to administer and generally well accepted by horses.  Omeprazole has demonstrated efficacy in the resolution ofboth naturally-occurring and NSAID-induced gastric ulcers in horses.(103.104 in Sanchez)  A single dose has also produced an increase in gastric pH in clinically ill neonatal foals<ref>Javsicas, L.H, Sanchez, L.C (2008) The effect of omeprazole paste on intragastric pH in clinically ill neonatal foals.  ''Equine Vet J'', 40(1):41-4.</ref> and has contributed to ulcer healing in neonates.<ref>MacAllister, C.G, Sifferman, R.L, McClure, S.R ''et al.'' (1999) Effects of omeprazole paste on healing of spontaneous gastric ulcers in horses and foals: a field trial.  ''Equine Vet J Suppl'', 77-80.  In: Sanchez, L.C (2010) 'Diseases Of The Stomach' in  Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref>  A potential concern is that altering gastric pH may encourage bacterial overgrowth.  Thus further work is needed to evaluate the long-term safety of omeprazole in horses and particularly, foals.<ref name="Vatistas">Vatistas, N.J, Snyder, J.R, Nieto, J, Thompson, D, Pollmeier, M, Holstes, J (1999) Acceptability of a paste formulation and efficacy of high dose omeprazole in healing gastric ulcers in horses maintained in race training.  ''Equine Vet J Suppl'', 29:71-76.</ref>

====Antacids====

====Antacids====

====Mucosal protectants====

====Mucosal protectants====

Sucralfate is a complex salt of sucrose and aluminium hydroxide.  It is thought to promote ulcer healing via several mechanisms: adherence to ulcerated mucosa, stimulation of mucus secretion, pepsin inibition, increasing prostgalandin E synthesis and enhancing the local production of epidermal growth factor.<ref name="Sanchez">Sanchez, L.C (2010) 'Diseases Of The Stomach' in  Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref>  It has been used effectively to treat and prevent stress-induced ulcers in man and has been recommended at 10-20mg/kg three times daily for the treatment of glandular ulcers in horses.<ref>Murray, M.J (1994) Gastric ulcers in adult horses.  ''Comp Cont Educ Pract Vet'', 16:792-794,797.  In: Orsini, J (2000) Tutorial Article Gastric ulceration in the mature horse: a review. ''Equine Vet Educ'', 12(1):24-27.</ref>

Sucralfate is a complex salt of sucrose and aluminium hydroxide.  It is thought to promote ulcer healing via several mechanisms: adherence to ulcerated mucosa, stimulation of mucus secretion, pepsin inibition, increasing prostgalandin E synthesis and enhancing the local production of epidermal growth factor.<ref name="Sanchez">Sanchez, L.C (2010) 'Diseases Of The Stomach' in  Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref>  It has been used effectively to treat and prevent stress-induced ulcers in man and has been recommended at 10-20mg/kg three times daily for the treatment of glandular ulcers in horses.<ref>Murray, M.J (1994) Gastric ulcers in adult horses.  ''Comp Cont Educ Pract Vet'', 16:792-794,797.  In: Orsini, J (2000) Tutorial Article Gastric ulceration in the mature horse: a review. ''Equine Vet Educ'', 12(1):24-27.</ref>  However, the effect of sucralfate on equine squamous gastric ulcers remains inconclusive<ref name="EGUC">The Equine Gastric Ulcer Council (1999) Tutorial Article: Recommendations for the diagnosis and treatment of equine gastric ulcer syndrome (EGUS).  ''Equine Vet Educ'', 11(5):262-272.</ref> and the product may be ineffective in the alkaline conditions created by acid suppression agents.(123-125 in Sanchez)

  However, the effect of sucralfate on equine squamous gastric ulcers remains inconclusive<ref name="EGUC">The Equine Gastric Ulcer Council (1999) Tutorial Article: Recommendations for the diagnosis and treatment of equine gastric ulcer syndrome (EGUS).  ''Equine Vet Educ'', 11(5):262-272.</ref> and the product may be ineffective in the alkaline conditions created by acid suppression agents.(123-125 in Sanchez)

====Prostaglandin analogues====

====Prostaglandin analogues====

   

   

Synthetic prostaglandin E1 analogues are believed to inihibit gastric acid secretion and enhance mucosal cytoprotection(127 in Sanchez).  Misoprostol has been an effective agent in the treatment of human gastric and duodenal ulcers and at 5µg/kg has been shown to increase gastric pH in horses (128 in Sanchez). Although contraindicated in pregnant mares, Misoprostol may be beneficial for mucosal recovery in the face of flunixin treatment.(129 in Sanchez)

Synthetic prostaglandin E1 analogues are believed to inihibit gastric acid secretion and enhance mucosal cytoprotection.<ref>Leandro, G, Pilotto, A, Franceschi, M ''et al.'' (2001) Prevention of acute NSAID-related gastroduodenal damage: a meta-analysis fo controlled clinical trials.  ''Dig Dis Sci'', 46:1924-1936.  In: Sanchez, L.C (2010) 'Diseases Of The Stomach' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref> Misoprostol has been an effective agent in the treatment of human gastric and duodenal ulcers and at 5µg/kg has been shown to increase gastric pH in horses.<ref>Sangiah, S, MacAllister, C.C, Amouzadeh, H.R (1989) Effects of misoprostol and omeprazole on basal gastric pH and free acid content in horses.  ''Res Vet Sci'', 47:350-354.  In: Sanchez, L.C (2010) 'Diseases Of The Stomach' in  Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref> Although contraindicated in pregnant mares, Misoprostol may be beneficial for mucosal recovery in the face of flunixin treatment.<ref>Tomlinson, J.E, Blikslager, A.T (2005) Effects of cyclooxygenase inhibitors flunixin and deracoxib on permeability of ischaemic-injured equine jejunum.  ''Equine Vet J'', 37:75-80.  In: Sanchez, L.C (2010) 'Diseases Of The Stomach' in Reed, S.M, Bayly, W.M. and Sellon, D.C (2010) '''Equine Internal Medicine''' (Third Edition), Saunders, Chapter 15.</ref>

====Gastric prokinetics====

====Gastric prokinetics====