Omeprazole Exposure Before Referral in Dogs with Chronic Inflammatory Enteropathy: A Retrospective Observational Single-Centre Study

Omeprazole, a proton pump inhibitor, is widely used in veterinary medicine, although it may be frequently prescribed for conditions in which evidence of benefit is limited. This retrospective observational single-centre study evaluated omeprazole exposure before referral in dogs subsequently diagnosed with chronic inflammatory enteropathy. Medical records from 151 dogs were reviewed, including omeprazole exposure during the six months preceding referral, documented indication, dose and administration frequency. Indications were classified according to American College of Veterinary Internal Medicine consensus recommendations. Overall, 83/151 dogs (55.0%; 95% CI, 47.0–62.7%) had documented omeprazole exposure within six months of referral. Of these, 30/83 (36.1%; 95% CI, 26.6–46.9%) had a documented consensus-consistent indication, whereas 53/83 (63.9%; 95% CI, 53.1–73.4%) did not. Non-specific gastrointestinal signs were the most common documented indication (42/83; 50.6%), followed by suspected gastrointestinal bleeding or gastrointestinal ulceration or erosion (21/83; 25.3%) and suspected gastro-oesophageal reflux or reflux-associated oesophagitis (9/83; 10.8%). Among dogs with a clearly documented once or twice daily oral dosing regimen, once daily administration was more common than twice daily administration (38/65; 58.5% versus 27/65; 41.5%). Omeprazole exposure was common before referral, and a substantial proportion of exposed dogs had no documented indication consistent with ACVIM consensus recommendations. Interpretation was limited by the retrospective design and dependence on the completeness of referring veterinary clinical records.