Use of rabbits for GI drug absorption studies.

A novel procedure to control the stomach emptying rate in rabbits is presented. Rabbits were given a special solid diet for 1 week, and then the gastric contents were washed out with saline. Then the rabbits were muzzled to prevent coprophagy during the night. Fifty grams of special soft diet given to the "stomach-emptying-controlled" rabbit transferred exponentially from the stomach into the small intestine and almost disappeared from the stomach within 5 hr. Griseofulvin, indomethacin, or nalidixic acid was administered in a hard gelatin capsule or tablet, with subsequent feeding of a special soft diet. Good correlations were observed between the plasma level-time curves of these drugs in the stomach-emptying-controlled rabbits and in human subjects.