Effect of flunixin meglumine and cimetidine hydrochloride on the pH in the third compartment of the stomach of llamas.

A Tigon fistula was surgically implanted into the third compartment of the stomach of 5 llamas to allow measurement of gastric pH. The llamas were allotted into 2 groups and given flunixin meglumine or cimetidine hydrochloride for 3 days. After 4 days without treatment, the drugs given to each group were reversed. Measurements of gastric pH were taken every 30 minutes for 6 hours, using an automated pH meter. The pH measurements after drug administration were compared with measurements obtained during a pretreatment control period. Gastric pH during pretreatment control periods had a mean of 1.43 +/- 0.063 (mean +/- SE). The use of flunixin did not significantly decrease gastric pH, compared with pretreatment controls. Gastric pH was significantly higher within the first 30 minutes after administering cimetidine, compared with pretreatment controls, but this difference disappeared at all later times.