title: Efficacy of omeprazole powder paste or enteric-coated formulation in healing of gastric ulcers in horses.
abstract: BACKGROUND
  GastroGard, an omeprazole powder paste formulation, is considered the standard treatment for gastric ulcers in horses and is highly effective. Gastrozol, an enteric-coated omeprazole formulation for horses, has recently become available, but efficacy data are controversial and sparse.
  
  
  OBJECTIVE
  To investigate the efficacy of GastroGard and Gastrozol at labeled doses (4 and 1 mg of omeprazole per kg bwt, respectively, PO q24h) in healing of gastric ulcers.
  
  
  METHODS
  40 horses; 9.5 ± 4.6 years; 491 ± 135 kg.
  
  
  METHODS
  Prospective, randomized, blinded study. Horses with an ulcer score ≥1 (Equine Gastric Ulcer Council) were randomly divided into 2 groups and treated for 2 weeks each with GastroGard followed by Gastrozol (A) or vice versa (B). After 2 and 4 weeks, scoring was repeated and compared with baseline. Plasma omeprazole concentrations were measured on the first day of treatment after administration of GastroGard (n = 5) or Gastrozol (n = 5).
  
  
  RESULTS
  Compared with baseline (squamous score (A) 1.65 ± 0.11, (B) 1.98 ± 0.11), ulcer scores at 2 weeks ((A) 0.89 ± 0.11, (B) 1.01 ± 0.11) and 4 weeks ((A) 1.10 ± 0.12, (B) 0.80 ± 0.12) had significantly decreased in both groups (P < .001), independent of treatment (P = .7). Plasma omeprazole concentrations were significantly higher after GastroGard compared with Gastrozol administration (AUCGG = 2856 (1405-4576) ng/mL × h, AUCGZ = 604 (430-1609) ng/mL × h; P = .03). The bioavailability for Gastrozol was 1.26 (95% CI 0.56-2.81) times higher than for GastroGard.
  
  
  CONCLUSIONS
  Both Gastrozol and GastroGard, combined with appropriate environmental changes, promote healing of gastric ulcers in horses. However, despite enteric coating of Gastrozol, plasma omeprazole concentrations after single labeled doses were significantly higher with GastroGard.
authors.affiliation: Equine Department, Vetsuisse Faculty, Clinic for Equine Internal Medicine, University of Zurich, Zurich, Switzerland.
authors.forename: K
authors.initials: K
authors.lastname: Birkmann
authors.forename: H K
authors.initials: HK
authors.lastname: Junge
authors.forename: E
authors.initials: E
authors.lastname: Maischberger
authors.forename: M
authors.initials: M
authors.lastname: Wehrli Eser
authors.forename: C C
authors.initials: CC
authors.lastname: Schwarzwald
mesh_terms: D000818:Animals; D000897:Anti-Ulcer Agents / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use*; D005260:Female; D006734:Horse Diseases / Q000188:drug therapy*; D006736:Horses; D008297:Male; D009824:Ointments / Q000627:therapeutic use; D009853:Omeprazole / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use*; D011208:Powders / Q000627:therapeutic use; D013276:Stomach Ulcer / Q000188:drug therapy / Q000662:veterinary*; D013608:Tablets, Enteric-Coated / Q000627:therapeutic use
chemical_list: D000897:Anti-Ulcer Agents; D009824:Ointments; D011208:Powders; D013608:Tablets, Enteric-Coated; D009853:Omeprazole
keywords: EGUS; GastroGard; Gastroenterology; Gastrozol