MISMATCH OF DUODENAL DELIVERIES OF DIETARY-FAT AND PANCREATIN FROM ENTERICALLY COATED MICROSPHERES

Gastric emptying of dietary fat is affected by both chemical and physi cal factors; but when ingested as a free oil or an aqueous emulsion, f at may empty most rapidly immediately after the meal. In contrast, gas tric transit of 1- to 3-mm spheres (like those of enterically coated p ancreatins) is known to vary inversely with sphere diameter; and spher es leave the stomach initially slowly, if their diameter is greater th an or equal to 1.6 mm. Our objective was to determine whether 2-mm mic rospheres of Pancrease would empty much more slowly than free or emuls ified oil and whether 1.2-mm microspheres of Creon would empty as fast as free oil. We used a gamma camera to track the concurrent gastric e mptying of I-123-labeled oil and In-113m-labeled spheres of Pancrease or Creon in pancreatic-insufficient subjects with cystic fibrosis who ingested 20 g of free oil in spaghetti meals or 20 g of oil emulsified in a milk meal. We found that either type of oil emptied rapidly init ially but slowed later, whereas either dosage form emptied slowly init ially but rapidly later. Unexpectedly, the smaller spheres of Creon em ptied about the same as Pancrease did after the spaghetti meal. For ex ample, 50% of oil but <25% of either dosage form had left the stomach by 90 min after the meals. Both dosage forms were lipophilic, forming aggregates in vitro. We concluded that the gastric emptying of either dosage form frequently lagged behind the emptying of oil from ordinary meals. We speculated that the similar transits of the 1.2-mm Creon an d the 2-mm Pancrease resulted from aggregation of these microspheres i n the presence of free oil.